xref: /freebsd/sys/vm/uma_core.c (revision 3f0efe05432b1633991114ca4ca330102a561959)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2002-2019 Jeffrey Roberson <jeff@FreeBSD.org>
5  * Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org>
6  * Copyright (c) 2004-2006 Robert N. M. Watson
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice unmodified, this list of conditions, and the following
14  *    disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 /*
32  * uma_core.c  Implementation of the Universal Memory allocator
33  *
34  * This allocator is intended to replace the multitude of similar object caches
35  * in the standard FreeBSD kernel.  The intent is to be flexible as well as
36  * efficient.  A primary design goal is to return unused memory to the rest of
37  * the system.  This will make the system as a whole more flexible due to the
38  * ability to move memory to subsystems which most need it instead of leaving
39  * pools of reserved memory unused.
40  *
41  * The basic ideas stem from similar slab/zone based allocators whose algorithms
42  * are well known.
43  *
44  */
45 
46 /*
47  * TODO:
48  *	- Improve memory usage for large allocations
49  *	- Investigate cache size adjustments
50  */
51 
52 #include <sys/cdefs.h>
53 #include "opt_ddb.h"
54 #include "opt_param.h"
55 #include "opt_vm.h"
56 
57 #include <sys/param.h>
58 #include <sys/systm.h>
59 #include <sys/asan.h>
60 #include <sys/bitset.h>
61 #include <sys/domainset.h>
62 #include <sys/eventhandler.h>
63 #include <sys/kernel.h>
64 #include <sys/types.h>
65 #include <sys/limits.h>
66 #include <sys/queue.h>
67 #include <sys/malloc.h>
68 #include <sys/ktr.h>
69 #include <sys/lock.h>
70 #include <sys/msan.h>
71 #include <sys/mutex.h>
72 #include <sys/proc.h>
73 #include <sys/random.h>
74 #include <sys/rwlock.h>
75 #include <sys/sbuf.h>
76 #include <sys/sched.h>
77 #include <sys/sleepqueue.h>
78 #include <sys/smp.h>
79 #include <sys/smr.h>
80 #include <sys/sysctl.h>
81 #include <sys/taskqueue.h>
82 #include <sys/vmmeter.h>
83 
84 #include <vm/vm.h>
85 #include <vm/vm_param.h>
86 #include <vm/vm_domainset.h>
87 #include <vm/vm_object.h>
88 #include <vm/vm_page.h>
89 #include <vm/vm_pageout.h>
90 #include <vm/vm_phys.h>
91 #include <vm/vm_pagequeue.h>
92 #include <vm/vm_map.h>
93 #include <vm/vm_kern.h>
94 #include <vm/vm_extern.h>
95 #include <vm/vm_dumpset.h>
96 #include <vm/uma.h>
97 #include <vm/uma_int.h>
98 #include <vm/uma_dbg.h>
99 
100 #include <ddb/ddb.h>
101 
102 #ifdef DEBUG_MEMGUARD
103 #include <vm/memguard.h>
104 #endif
105 
106 #include <machine/md_var.h>
107 
108 #ifdef INVARIANTS
109 #define	UMA_ALWAYS_CTORDTOR	1
110 #else
111 #define	UMA_ALWAYS_CTORDTOR	0
112 #endif
113 
114 /*
115  * This is the zone and keg from which all zones are spawned.
116  */
117 static uma_zone_t kegs;
118 static uma_zone_t zones;
119 
120 /*
121  * On INVARIANTS builds, the slab contains a second bitset of the same size,
122  * "dbg_bits", which is laid out immediately after us_free.
123  */
124 #ifdef INVARIANTS
125 #define	SLAB_BITSETS	2
126 #else
127 #define	SLAB_BITSETS	1
128 #endif
129 
130 /*
131  * These are the two zones from which all offpage uma_slab_ts are allocated.
132  *
133  * One zone is for slab headers that can represent a larger number of items,
134  * making the slabs themselves more efficient, and the other zone is for
135  * headers that are smaller and represent fewer items, making the headers more
136  * efficient.
137  */
138 #define	SLABZONE_SIZE(setsize)					\
139     (sizeof(struct uma_hash_slab) + BITSET_SIZE(setsize) * SLAB_BITSETS)
140 #define	SLABZONE0_SETSIZE	(PAGE_SIZE / 16)
141 #define	SLABZONE1_SETSIZE	SLAB_MAX_SETSIZE
142 #define	SLABZONE0_SIZE	SLABZONE_SIZE(SLABZONE0_SETSIZE)
143 #define	SLABZONE1_SIZE	SLABZONE_SIZE(SLABZONE1_SETSIZE)
144 static uma_zone_t slabzones[2];
145 
146 /*
147  * The initial hash tables come out of this zone so they can be allocated
148  * prior to malloc coming up.
149  */
150 static uma_zone_t hashzone;
151 
152 /* The boot-time adjusted value for cache line alignment. */
153 static unsigned int uma_cache_align_mask = 64 - 1;
154 
155 static MALLOC_DEFINE(M_UMAHASH, "UMAHash", "UMA Hash Buckets");
156 static MALLOC_DEFINE(M_UMA, "UMA", "UMA Misc");
157 
158 /*
159  * Are we allowed to allocate buckets?
160  */
161 static int bucketdisable = 1;
162 
163 /* Linked list of all kegs in the system */
164 static LIST_HEAD(,uma_keg) uma_kegs = LIST_HEAD_INITIALIZER(uma_kegs);
165 
166 /* Linked list of all cache-only zones in the system */
167 static LIST_HEAD(,uma_zone) uma_cachezones =
168     LIST_HEAD_INITIALIZER(uma_cachezones);
169 
170 /*
171  * Mutex for global lists: uma_kegs, uma_cachezones, and the per-keg list of
172  * zones.
173  */
174 static struct rwlock_padalign __exclusive_cache_line uma_rwlock;
175 
176 static struct sx uma_reclaim_lock;
177 
178 /*
179  * First available virual address for boot time allocations.
180  */
181 static vm_offset_t bootstart;
182 static vm_offset_t bootmem;
183 
184 /*
185  * kmem soft limit, initialized by uma_set_limit().  Ensure that early
186  * allocations don't trigger a wakeup of the reclaim thread.
187  */
188 unsigned long uma_kmem_limit = LONG_MAX;
189 SYSCTL_ULONG(_vm, OID_AUTO, uma_kmem_limit, CTLFLAG_RD, &uma_kmem_limit, 0,
190     "UMA kernel memory soft limit");
191 unsigned long uma_kmem_total;
192 SYSCTL_ULONG(_vm, OID_AUTO, uma_kmem_total, CTLFLAG_RD, &uma_kmem_total, 0,
193     "UMA kernel memory usage");
194 
195 /* Is the VM done starting up? */
196 static enum {
197 	BOOT_COLD,
198 	BOOT_KVA,
199 	BOOT_PCPU,
200 	BOOT_RUNNING,
201 	BOOT_SHUTDOWN,
202 } booted = BOOT_COLD;
203 
204 /*
205  * This is the handle used to schedule events that need to happen
206  * outside of the allocation fast path.
207  */
208 static struct timeout_task uma_timeout_task;
209 #define	UMA_TIMEOUT	20		/* Seconds for callout interval. */
210 
211 /*
212  * This structure is passed as the zone ctor arg so that I don't have to create
213  * a special allocation function just for zones.
214  */
215 struct uma_zctor_args {
216 	const char *name;
217 	size_t size;
218 	uma_ctor ctor;
219 	uma_dtor dtor;
220 	uma_init uminit;
221 	uma_fini fini;
222 	uma_import import;
223 	uma_release release;
224 	void *arg;
225 	uma_keg_t keg;
226 	int align;
227 	uint32_t flags;
228 };
229 
230 struct uma_kctor_args {
231 	uma_zone_t zone;
232 	size_t size;
233 	uma_init uminit;
234 	uma_fini fini;
235 	int align;
236 	uint32_t flags;
237 };
238 
239 struct uma_bucket_zone {
240 	uma_zone_t	ubz_zone;
241 	const char	*ubz_name;
242 	int		ubz_entries;	/* Number of items it can hold. */
243 	int		ubz_maxsize;	/* Maximum allocation size per-item. */
244 };
245 
246 /*
247  * Compute the actual number of bucket entries to pack them in power
248  * of two sizes for more efficient space utilization.
249  */
250 #define	BUCKET_SIZE(n)						\
251     (((sizeof(void *) * (n)) - sizeof(struct uma_bucket)) / sizeof(void *))
252 
253 #define	BUCKET_MAX	BUCKET_SIZE(256)
254 
255 struct uma_bucket_zone bucket_zones[] = {
256 	/* Literal bucket sizes. */
257 	{ NULL, "2 Bucket", 2, 4096 },
258 	{ NULL, "4 Bucket", 4, 3072 },
259 	{ NULL, "8 Bucket", 8, 2048 },
260 	{ NULL, "16 Bucket", 16, 1024 },
261 	/* Rounded down power of 2 sizes for efficiency. */
262 	{ NULL, "32 Bucket", BUCKET_SIZE(32), 512 },
263 	{ NULL, "64 Bucket", BUCKET_SIZE(64), 256 },
264 	{ NULL, "128 Bucket", BUCKET_SIZE(128), 128 },
265 	{ NULL, "256 Bucket", BUCKET_SIZE(256), 64 },
266 	{ NULL, NULL, 0}
267 };
268 
269 /*
270  * Flags and enumerations to be passed to internal functions.
271  */
272 enum zfreeskip {
273 	SKIP_NONE =	0,
274 	SKIP_CNT =	0x00000001,
275 	SKIP_DTOR =	0x00010000,
276 	SKIP_FINI =	0x00020000,
277 };
278 
279 /* Prototypes.. */
280 
281 void	uma_startup1(vm_offset_t);
282 void	uma_startup2(void);
283 
284 static void *noobj_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
285 static void *page_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
286 static void *pcpu_page_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
287 static void *startup_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
288 static void *contig_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
289 static void page_free(void *, vm_size_t, uint8_t);
290 static void pcpu_page_free(void *, vm_size_t, uint8_t);
291 static uma_slab_t keg_alloc_slab(uma_keg_t, uma_zone_t, int, int, int);
292 static void cache_drain(uma_zone_t);
293 static void bucket_drain(uma_zone_t, uma_bucket_t);
294 static void bucket_cache_reclaim(uma_zone_t zone, bool, int);
295 static bool bucket_cache_reclaim_domain(uma_zone_t, bool, bool, int);
296 static int keg_ctor(void *, int, void *, int);
297 static void keg_dtor(void *, int, void *);
298 static void keg_drain(uma_keg_t keg, int domain);
299 static int zone_ctor(void *, int, void *, int);
300 static void zone_dtor(void *, int, void *);
301 static inline void item_dtor(uma_zone_t zone, void *item, int size,
302     void *udata, enum zfreeskip skip);
303 static int zero_init(void *, int, int);
304 static void zone_free_bucket(uma_zone_t zone, uma_bucket_t bucket, void *udata,
305     int itemdomain, bool ws);
306 static void zone_foreach(void (*zfunc)(uma_zone_t, void *), void *);
307 static void zone_foreach_unlocked(void (*zfunc)(uma_zone_t, void *), void *);
308 static void zone_timeout(uma_zone_t zone, void *);
309 static int hash_alloc(struct uma_hash *, u_int);
310 static int hash_expand(struct uma_hash *, struct uma_hash *);
311 static void hash_free(struct uma_hash *hash);
312 static void uma_timeout(void *, int);
313 static void uma_shutdown(void);
314 static void *zone_alloc_item(uma_zone_t, void *, int, int);
315 static void zone_free_item(uma_zone_t, void *, void *, enum zfreeskip);
316 static int zone_alloc_limit(uma_zone_t zone, int count, int flags);
317 static void zone_free_limit(uma_zone_t zone, int count);
318 static void bucket_enable(void);
319 static void bucket_init(void);
320 static uma_bucket_t bucket_alloc(uma_zone_t zone, void *, int);
321 static void bucket_free(uma_zone_t zone, uma_bucket_t, void *);
322 static void bucket_zone_drain(int domain);
323 static uma_bucket_t zone_alloc_bucket(uma_zone_t, void *, int, int);
324 static void *slab_alloc_item(uma_keg_t keg, uma_slab_t slab);
325 static void slab_free_item(uma_zone_t zone, uma_slab_t slab, void *item);
326 static size_t slab_sizeof(int nitems);
327 static uma_keg_t uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit,
328     uma_fini fini, int align, uint32_t flags);
329 static int zone_import(void *, void **, int, int, int);
330 static void zone_release(void *, void **, int);
331 static bool cache_alloc(uma_zone_t, uma_cache_t, void *, int);
332 static bool cache_free(uma_zone_t, uma_cache_t, void *, int);
333 
334 static int sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS);
335 static int sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS);
336 static int sysctl_handle_uma_zone_allocs(SYSCTL_HANDLER_ARGS);
337 static int sysctl_handle_uma_zone_frees(SYSCTL_HANDLER_ARGS);
338 static int sysctl_handle_uma_zone_flags(SYSCTL_HANDLER_ARGS);
339 static int sysctl_handle_uma_slab_efficiency(SYSCTL_HANDLER_ARGS);
340 static int sysctl_handle_uma_zone_items(SYSCTL_HANDLER_ARGS);
341 
342 static uint64_t uma_zone_get_allocs(uma_zone_t zone);
343 
344 static SYSCTL_NODE(_vm, OID_AUTO, debug, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
345     "Memory allocation debugging");
346 
347 #ifdef INVARIANTS
348 static uint64_t uma_keg_get_allocs(uma_keg_t zone);
349 static inline struct noslabbits *slab_dbg_bits(uma_slab_t slab, uma_keg_t keg);
350 
351 static bool uma_dbg_kskip(uma_keg_t keg, void *mem);
352 static bool uma_dbg_zskip(uma_zone_t zone, void *mem);
353 static void uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item);
354 static void uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item);
355 
356 static u_int dbg_divisor = 1;
357 SYSCTL_UINT(_vm_debug, OID_AUTO, divisor,
358     CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &dbg_divisor, 0,
359     "Debug & thrash every this item in memory allocator");
360 
361 static counter_u64_t uma_dbg_cnt = EARLY_COUNTER;
362 static counter_u64_t uma_skip_cnt = EARLY_COUNTER;
363 SYSCTL_COUNTER_U64(_vm_debug, OID_AUTO, trashed, CTLFLAG_RD,
364     &uma_dbg_cnt, "memory items debugged");
365 SYSCTL_COUNTER_U64(_vm_debug, OID_AUTO, skipped, CTLFLAG_RD,
366     &uma_skip_cnt, "memory items skipped, not debugged");
367 #endif
368 
369 SYSCTL_NODE(_vm, OID_AUTO, uma, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
370     "Universal Memory Allocator");
371 
372 SYSCTL_PROC(_vm, OID_AUTO, zone_count, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLTYPE_INT,
373     0, 0, sysctl_vm_zone_count, "I", "Number of UMA zones");
374 
375 SYSCTL_PROC(_vm, OID_AUTO, zone_stats, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLTYPE_STRUCT,
376     0, 0, sysctl_vm_zone_stats, "s,struct uma_type_header", "Zone Stats");
377 
378 static int zone_warnings = 1;
379 SYSCTL_INT(_vm, OID_AUTO, zone_warnings, CTLFLAG_RWTUN, &zone_warnings, 0,
380     "Warn when UMA zones becomes full");
381 
382 static int multipage_slabs = 1;
383 TUNABLE_INT("vm.debug.uma_multipage_slabs", &multipage_slabs);
384 SYSCTL_INT(_vm_debug, OID_AUTO, uma_multipage_slabs,
385     CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &multipage_slabs, 0,
386     "UMA may choose larger slab sizes for better efficiency");
387 
388 /*
389  * Select the slab zone for an offpage slab with the given maximum item count.
390  */
391 static inline uma_zone_t
392 slabzone(int ipers)
393 {
394 
395 	return (slabzones[ipers > SLABZONE0_SETSIZE]);
396 }
397 
398 /*
399  * This routine checks to see whether or not it's safe to enable buckets.
400  */
401 static void
402 bucket_enable(void)
403 {
404 
405 	KASSERT(booted >= BOOT_KVA, ("Bucket enable before init"));
406 	bucketdisable = vm_page_count_min();
407 }
408 
409 /*
410  * Initialize bucket_zones, the array of zones of buckets of various sizes.
411  *
412  * For each zone, calculate the memory required for each bucket, consisting
413  * of the header and an array of pointers.
414  */
415 static void
416 bucket_init(void)
417 {
418 	struct uma_bucket_zone *ubz;
419 	int size;
420 
421 	for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++) {
422 		size = roundup(sizeof(struct uma_bucket), sizeof(void *));
423 		size += sizeof(void *) * ubz->ubz_entries;
424 		ubz->ubz_zone = uma_zcreate(ubz->ubz_name, size,
425 		    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
426 		    UMA_ZONE_MTXCLASS | UMA_ZFLAG_BUCKET |
427 		    UMA_ZONE_FIRSTTOUCH);
428 	}
429 }
430 
431 /*
432  * Given a desired number of entries for a bucket, return the zone from which
433  * to allocate the bucket.
434  */
435 static struct uma_bucket_zone *
436 bucket_zone_lookup(int entries)
437 {
438 	struct uma_bucket_zone *ubz;
439 
440 	for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
441 		if (ubz->ubz_entries >= entries)
442 			return (ubz);
443 	ubz--;
444 	return (ubz);
445 }
446 
447 static int
448 bucket_select(int size)
449 {
450 	struct uma_bucket_zone *ubz;
451 
452 	ubz = &bucket_zones[0];
453 	if (size > ubz->ubz_maxsize)
454 		return MAX((ubz->ubz_maxsize * ubz->ubz_entries) / size, 1);
455 
456 	for (; ubz->ubz_entries != 0; ubz++)
457 		if (ubz->ubz_maxsize < size)
458 			break;
459 	ubz--;
460 	return (ubz->ubz_entries);
461 }
462 
463 static uma_bucket_t
464 bucket_alloc(uma_zone_t zone, void *udata, int flags)
465 {
466 	struct uma_bucket_zone *ubz;
467 	uma_bucket_t bucket;
468 
469 	/*
470 	 * Don't allocate buckets early in boot.
471 	 */
472 	if (__predict_false(booted < BOOT_KVA))
473 		return (NULL);
474 
475 	/*
476 	 * To limit bucket recursion we store the original zone flags
477 	 * in a cookie passed via zalloc_arg/zfree_arg.  This allows the
478 	 * NOVM flag to persist even through deep recursions.  We also
479 	 * store ZFLAG_BUCKET once we have recursed attempting to allocate
480 	 * a bucket for a bucket zone so we do not allow infinite bucket
481 	 * recursion.  This cookie will even persist to frees of unused
482 	 * buckets via the allocation path or bucket allocations in the
483 	 * free path.
484 	 */
485 	if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
486 		udata = (void *)(uintptr_t)zone->uz_flags;
487 	else {
488 		if ((uintptr_t)udata & UMA_ZFLAG_BUCKET)
489 			return (NULL);
490 		udata = (void *)((uintptr_t)udata | UMA_ZFLAG_BUCKET);
491 	}
492 	if (((uintptr_t)udata & UMA_ZONE_VM) != 0)
493 		flags |= M_NOVM;
494 	ubz = bucket_zone_lookup(atomic_load_16(&zone->uz_bucket_size));
495 	if (ubz->ubz_zone == zone && (ubz + 1)->ubz_entries != 0)
496 		ubz++;
497 	bucket = uma_zalloc_arg(ubz->ubz_zone, udata, flags);
498 	if (bucket) {
499 #ifdef INVARIANTS
500 		bzero(bucket->ub_bucket, sizeof(void *) * ubz->ubz_entries);
501 #endif
502 		bucket->ub_cnt = 0;
503 		bucket->ub_entries = min(ubz->ubz_entries,
504 		    zone->uz_bucket_size_max);
505 		bucket->ub_seq = SMR_SEQ_INVALID;
506 		CTR3(KTR_UMA, "bucket_alloc: zone %s(%p) allocated bucket %p",
507 		    zone->uz_name, zone, bucket);
508 	}
509 
510 	return (bucket);
511 }
512 
513 static void
514 bucket_free(uma_zone_t zone, uma_bucket_t bucket, void *udata)
515 {
516 	struct uma_bucket_zone *ubz;
517 
518 	if (bucket->ub_cnt != 0)
519 		bucket_drain(zone, bucket);
520 
521 	KASSERT(bucket->ub_cnt == 0,
522 	    ("bucket_free: Freeing a non free bucket."));
523 	KASSERT(bucket->ub_seq == SMR_SEQ_INVALID,
524 	    ("bucket_free: Freeing an SMR bucket."));
525 	if ((zone->uz_flags & UMA_ZFLAG_BUCKET) == 0)
526 		udata = (void *)(uintptr_t)zone->uz_flags;
527 	ubz = bucket_zone_lookup(bucket->ub_entries);
528 	uma_zfree_arg(ubz->ubz_zone, bucket, udata);
529 }
530 
531 static void
532 bucket_zone_drain(int domain)
533 {
534 	struct uma_bucket_zone *ubz;
535 
536 	for (ubz = &bucket_zones[0]; ubz->ubz_entries != 0; ubz++)
537 		uma_zone_reclaim_domain(ubz->ubz_zone, UMA_RECLAIM_DRAIN,
538 		    domain);
539 }
540 
541 #ifdef KASAN
542 _Static_assert(UMA_SMALLEST_UNIT % KASAN_SHADOW_SCALE == 0,
543     "Base UMA allocation size not a multiple of the KASAN scale factor");
544 
545 static void
546 kasan_mark_item_valid(uma_zone_t zone, void *item)
547 {
548 	void *pcpu_item;
549 	size_t sz, rsz;
550 	int i;
551 
552 	if ((zone->uz_flags & UMA_ZONE_NOKASAN) != 0)
553 		return;
554 
555 	sz = zone->uz_size;
556 	rsz = roundup2(sz, KASAN_SHADOW_SCALE);
557 	if ((zone->uz_flags & UMA_ZONE_PCPU) == 0) {
558 		kasan_mark(item, sz, rsz, KASAN_GENERIC_REDZONE);
559 	} else {
560 		pcpu_item = zpcpu_base_to_offset(item);
561 		for (i = 0; i <= mp_maxid; i++)
562 			kasan_mark(zpcpu_get_cpu(pcpu_item, i), sz, rsz,
563 			    KASAN_GENERIC_REDZONE);
564 	}
565 }
566 
567 static void
568 kasan_mark_item_invalid(uma_zone_t zone, void *item)
569 {
570 	void *pcpu_item;
571 	size_t sz;
572 	int i;
573 
574 	if ((zone->uz_flags & UMA_ZONE_NOKASAN) != 0)
575 		return;
576 
577 	sz = roundup2(zone->uz_size, KASAN_SHADOW_SCALE);
578 	if ((zone->uz_flags & UMA_ZONE_PCPU) == 0) {
579 		kasan_mark(item, 0, sz, KASAN_UMA_FREED);
580 	} else {
581 		pcpu_item = zpcpu_base_to_offset(item);
582 		for (i = 0; i <= mp_maxid; i++)
583 			kasan_mark(zpcpu_get_cpu(pcpu_item, i), 0, sz,
584 			    KASAN_UMA_FREED);
585 	}
586 }
587 
588 static void
589 kasan_mark_slab_valid(uma_keg_t keg, void *mem)
590 {
591 	size_t sz;
592 
593 	if ((keg->uk_flags & UMA_ZONE_NOKASAN) == 0) {
594 		sz = keg->uk_ppera * PAGE_SIZE;
595 		kasan_mark(mem, sz, sz, 0);
596 	}
597 }
598 
599 static void
600 kasan_mark_slab_invalid(uma_keg_t keg, void *mem)
601 {
602 	size_t sz;
603 
604 	if ((keg->uk_flags & UMA_ZONE_NOKASAN) == 0) {
605 		if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0)
606 			sz = keg->uk_ppera * PAGE_SIZE;
607 		else
608 			sz = keg->uk_pgoff;
609 		kasan_mark(mem, 0, sz, KASAN_UMA_FREED);
610 	}
611 }
612 #else /* !KASAN */
613 static void
614 kasan_mark_item_valid(uma_zone_t zone __unused, void *item __unused)
615 {
616 }
617 
618 static void
619 kasan_mark_item_invalid(uma_zone_t zone __unused, void *item __unused)
620 {
621 }
622 
623 static void
624 kasan_mark_slab_valid(uma_keg_t keg __unused, void *mem __unused)
625 {
626 }
627 
628 static void
629 kasan_mark_slab_invalid(uma_keg_t keg __unused, void *mem __unused)
630 {
631 }
632 #endif /* KASAN */
633 
634 #ifdef KMSAN
635 static inline void
636 kmsan_mark_item_uninitialized(uma_zone_t zone, void *item)
637 {
638 	void *pcpu_item;
639 	size_t sz;
640 	int i;
641 
642 	if ((zone->uz_flags &
643 	    (UMA_ZFLAG_CACHE | UMA_ZONE_SECONDARY | UMA_ZONE_MALLOC)) != 0) {
644 		/*
645 		 * Cache zones should not be instrumented by default, as UMA
646 		 * does not have enough information to do so correctly.
647 		 * Consumers can mark items themselves if it makes sense to do
648 		 * so.
649 		 *
650 		 * Items from secondary zones are initialized by the parent
651 		 * zone and thus cannot safely be marked by UMA.
652 		 *
653 		 * malloc zones are handled directly by malloc(9) and friends,
654 		 * since they can provide more precise origin tracking.
655 		 */
656 		return;
657 	}
658 	if (zone->uz_keg->uk_init != NULL) {
659 		/*
660 		 * By definition, initialized items cannot be marked.  The
661 		 * best we can do is mark items from these zones after they
662 		 * are freed to the keg.
663 		 */
664 		return;
665 	}
666 
667 	sz = zone->uz_size;
668 	if ((zone->uz_flags & UMA_ZONE_PCPU) == 0) {
669 		kmsan_orig(item, sz, KMSAN_TYPE_UMA, KMSAN_RET_ADDR);
670 		kmsan_mark(item, sz, KMSAN_STATE_UNINIT);
671 	} else {
672 		pcpu_item = zpcpu_base_to_offset(item);
673 		for (i = 0; i <= mp_maxid; i++) {
674 			kmsan_orig(zpcpu_get_cpu(pcpu_item, i), sz,
675 			    KMSAN_TYPE_UMA, KMSAN_RET_ADDR);
676 			kmsan_mark(zpcpu_get_cpu(pcpu_item, i), sz,
677 			    KMSAN_STATE_INITED);
678 		}
679 	}
680 }
681 #else /* !KMSAN */
682 static inline void
683 kmsan_mark_item_uninitialized(uma_zone_t zone __unused, void *item __unused)
684 {
685 }
686 #endif /* KMSAN */
687 
688 /*
689  * Acquire the domain lock and record contention.
690  */
691 static uma_zone_domain_t
692 zone_domain_lock(uma_zone_t zone, int domain)
693 {
694 	uma_zone_domain_t zdom;
695 	bool lockfail;
696 
697 	zdom = ZDOM_GET(zone, domain);
698 	lockfail = false;
699 	if (ZDOM_OWNED(zdom))
700 		lockfail = true;
701 	ZDOM_LOCK(zdom);
702 	/* This is unsynchronized.  The counter does not need to be precise. */
703 	if (lockfail && zone->uz_bucket_size < zone->uz_bucket_size_max)
704 		zone->uz_bucket_size++;
705 	return (zdom);
706 }
707 
708 /*
709  * Search for the domain with the least cached items and return it if it
710  * is out of balance with the preferred domain.
711  */
712 static __noinline int
713 zone_domain_lowest(uma_zone_t zone, int pref)
714 {
715 	long least, nitems, prefitems;
716 	int domain;
717 	int i;
718 
719 	prefitems = least = LONG_MAX;
720 	domain = 0;
721 	for (i = 0; i < vm_ndomains; i++) {
722 		nitems = ZDOM_GET(zone, i)->uzd_nitems;
723 		if (nitems < least) {
724 			domain = i;
725 			least = nitems;
726 		}
727 		if (domain == pref)
728 			prefitems = nitems;
729 	}
730 	if (prefitems < least * 2)
731 		return (pref);
732 
733 	return (domain);
734 }
735 
736 /*
737  * Search for the domain with the most cached items and return it or the
738  * preferred domain if it has enough to proceed.
739  */
740 static __noinline int
741 zone_domain_highest(uma_zone_t zone, int pref)
742 {
743 	long most, nitems;
744 	int domain;
745 	int i;
746 
747 	if (ZDOM_GET(zone, pref)->uzd_nitems > BUCKET_MAX)
748 		return (pref);
749 
750 	most = 0;
751 	domain = 0;
752 	for (i = 0; i < vm_ndomains; i++) {
753 		nitems = ZDOM_GET(zone, i)->uzd_nitems;
754 		if (nitems > most) {
755 			domain = i;
756 			most = nitems;
757 		}
758 	}
759 
760 	return (domain);
761 }
762 
763 /*
764  * Set the maximum imax value.
765  */
766 static void
767 zone_domain_imax_set(uma_zone_domain_t zdom, int nitems)
768 {
769 	long old;
770 
771 	old = zdom->uzd_imax;
772 	do {
773 		if (old >= nitems)
774 			return;
775 	} while (atomic_fcmpset_long(&zdom->uzd_imax, &old, nitems) == 0);
776 
777 	/*
778 	 * We are at new maximum, so do the last WSS update for the old
779 	 * bimin and prepare to measure next allocation batch.
780 	 */
781 	if (zdom->uzd_wss < old - zdom->uzd_bimin)
782 		zdom->uzd_wss = old - zdom->uzd_bimin;
783 	zdom->uzd_bimin = nitems;
784 }
785 
786 /*
787  * Attempt to satisfy an allocation by retrieving a full bucket from one of the
788  * zone's caches.  If a bucket is found the zone is not locked on return.
789  */
790 static uma_bucket_t
791 zone_fetch_bucket(uma_zone_t zone, uma_zone_domain_t zdom, bool reclaim)
792 {
793 	uma_bucket_t bucket;
794 	long cnt;
795 	int i;
796 	bool dtor = false;
797 
798 	ZDOM_LOCK_ASSERT(zdom);
799 
800 	if ((bucket = STAILQ_FIRST(&zdom->uzd_buckets)) == NULL)
801 		return (NULL);
802 
803 	/* SMR Buckets can not be re-used until readers expire. */
804 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0 &&
805 	    bucket->ub_seq != SMR_SEQ_INVALID) {
806 		if (!smr_poll(zone->uz_smr, bucket->ub_seq, false))
807 			return (NULL);
808 		bucket->ub_seq = SMR_SEQ_INVALID;
809 		dtor = (zone->uz_dtor != NULL) || UMA_ALWAYS_CTORDTOR;
810 		if (STAILQ_NEXT(bucket, ub_link) != NULL)
811 			zdom->uzd_seq = STAILQ_NEXT(bucket, ub_link)->ub_seq;
812 	}
813 	STAILQ_REMOVE_HEAD(&zdom->uzd_buckets, ub_link);
814 
815 	KASSERT(zdom->uzd_nitems >= bucket->ub_cnt,
816 	    ("%s: item count underflow (%ld, %d)",
817 	    __func__, zdom->uzd_nitems, bucket->ub_cnt));
818 	KASSERT(bucket->ub_cnt > 0,
819 	    ("%s: empty bucket in bucket cache", __func__));
820 	zdom->uzd_nitems -= bucket->ub_cnt;
821 
822 	if (reclaim) {
823 		/*
824 		 * Shift the bounds of the current WSS interval to avoid
825 		 * perturbing the estimates.
826 		 */
827 		cnt = lmin(zdom->uzd_bimin, bucket->ub_cnt);
828 		atomic_subtract_long(&zdom->uzd_imax, cnt);
829 		zdom->uzd_bimin -= cnt;
830 		zdom->uzd_imin -= lmin(zdom->uzd_imin, bucket->ub_cnt);
831 		if (zdom->uzd_limin >= bucket->ub_cnt) {
832 			zdom->uzd_limin -= bucket->ub_cnt;
833 		} else {
834 			zdom->uzd_limin = 0;
835 			zdom->uzd_timin = 0;
836 		}
837 	} else if (zdom->uzd_bimin > zdom->uzd_nitems) {
838 		zdom->uzd_bimin = zdom->uzd_nitems;
839 		if (zdom->uzd_imin > zdom->uzd_nitems)
840 			zdom->uzd_imin = zdom->uzd_nitems;
841 	}
842 
843 	ZDOM_UNLOCK(zdom);
844 	if (dtor)
845 		for (i = 0; i < bucket->ub_cnt; i++)
846 			item_dtor(zone, bucket->ub_bucket[i], zone->uz_size,
847 			    NULL, SKIP_NONE);
848 
849 	return (bucket);
850 }
851 
852 /*
853  * Insert a full bucket into the specified cache.  The "ws" parameter indicates
854  * whether the bucket's contents should be counted as part of the zone's working
855  * set.  The bucket may be freed if it exceeds the bucket limit.
856  */
857 static void
858 zone_put_bucket(uma_zone_t zone, int domain, uma_bucket_t bucket, void *udata,
859     const bool ws)
860 {
861 	uma_zone_domain_t zdom;
862 
863 	/* We don't cache empty buckets.  This can happen after a reclaim. */
864 	if (bucket->ub_cnt == 0)
865 		goto out;
866 	zdom = zone_domain_lock(zone, domain);
867 
868 	/*
869 	 * Conditionally set the maximum number of items.
870 	 */
871 	zdom->uzd_nitems += bucket->ub_cnt;
872 	if (__predict_true(zdom->uzd_nitems < zone->uz_bucket_max)) {
873 		if (ws) {
874 			zone_domain_imax_set(zdom, zdom->uzd_nitems);
875 		} else {
876 			/*
877 			 * Shift the bounds of the current WSS interval to
878 			 * avoid perturbing the estimates.
879 			 */
880 			atomic_add_long(&zdom->uzd_imax, bucket->ub_cnt);
881 			zdom->uzd_imin += bucket->ub_cnt;
882 			zdom->uzd_bimin += bucket->ub_cnt;
883 			zdom->uzd_limin += bucket->ub_cnt;
884 		}
885 		if (STAILQ_EMPTY(&zdom->uzd_buckets))
886 			zdom->uzd_seq = bucket->ub_seq;
887 
888 		/*
889 		 * Try to promote reuse of recently used items.  For items
890 		 * protected by SMR, try to defer reuse to minimize polling.
891 		 */
892 		if (bucket->ub_seq == SMR_SEQ_INVALID)
893 			STAILQ_INSERT_HEAD(&zdom->uzd_buckets, bucket, ub_link);
894 		else
895 			STAILQ_INSERT_TAIL(&zdom->uzd_buckets, bucket, ub_link);
896 		ZDOM_UNLOCK(zdom);
897 		return;
898 	}
899 	zdom->uzd_nitems -= bucket->ub_cnt;
900 	ZDOM_UNLOCK(zdom);
901 out:
902 	bucket_free(zone, bucket, udata);
903 }
904 
905 /* Pops an item out of a per-cpu cache bucket. */
906 static inline void *
907 cache_bucket_pop(uma_cache_t cache, uma_cache_bucket_t bucket)
908 {
909 	void *item;
910 
911 	CRITICAL_ASSERT(curthread);
912 
913 	bucket->ucb_cnt--;
914 	item = bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt];
915 #ifdef INVARIANTS
916 	bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] = NULL;
917 	KASSERT(item != NULL, ("uma_zalloc: Bucket pointer mangled."));
918 #endif
919 	cache->uc_allocs++;
920 
921 	return (item);
922 }
923 
924 /* Pushes an item into a per-cpu cache bucket. */
925 static inline void
926 cache_bucket_push(uma_cache_t cache, uma_cache_bucket_t bucket, void *item)
927 {
928 
929 	CRITICAL_ASSERT(curthread);
930 	KASSERT(bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] == NULL,
931 	    ("uma_zfree: Freeing to non free bucket index."));
932 
933 	bucket->ucb_bucket->ub_bucket[bucket->ucb_cnt] = item;
934 	bucket->ucb_cnt++;
935 	cache->uc_frees++;
936 }
937 
938 /*
939  * Unload a UMA bucket from a per-cpu cache.
940  */
941 static inline uma_bucket_t
942 cache_bucket_unload(uma_cache_bucket_t bucket)
943 {
944 	uma_bucket_t b;
945 
946 	b = bucket->ucb_bucket;
947 	if (b != NULL) {
948 		MPASS(b->ub_entries == bucket->ucb_entries);
949 		b->ub_cnt = bucket->ucb_cnt;
950 		bucket->ucb_bucket = NULL;
951 		bucket->ucb_entries = bucket->ucb_cnt = 0;
952 	}
953 
954 	return (b);
955 }
956 
957 static inline uma_bucket_t
958 cache_bucket_unload_alloc(uma_cache_t cache)
959 {
960 
961 	return (cache_bucket_unload(&cache->uc_allocbucket));
962 }
963 
964 static inline uma_bucket_t
965 cache_bucket_unload_free(uma_cache_t cache)
966 {
967 
968 	return (cache_bucket_unload(&cache->uc_freebucket));
969 }
970 
971 static inline uma_bucket_t
972 cache_bucket_unload_cross(uma_cache_t cache)
973 {
974 
975 	return (cache_bucket_unload(&cache->uc_crossbucket));
976 }
977 
978 /*
979  * Load a bucket into a per-cpu cache bucket.
980  */
981 static inline void
982 cache_bucket_load(uma_cache_bucket_t bucket, uma_bucket_t b)
983 {
984 
985 	CRITICAL_ASSERT(curthread);
986 	MPASS(bucket->ucb_bucket == NULL);
987 	MPASS(b->ub_seq == SMR_SEQ_INVALID);
988 
989 	bucket->ucb_bucket = b;
990 	bucket->ucb_cnt = b->ub_cnt;
991 	bucket->ucb_entries = b->ub_entries;
992 }
993 
994 static inline void
995 cache_bucket_load_alloc(uma_cache_t cache, uma_bucket_t b)
996 {
997 
998 	cache_bucket_load(&cache->uc_allocbucket, b);
999 }
1000 
1001 static inline void
1002 cache_bucket_load_free(uma_cache_t cache, uma_bucket_t b)
1003 {
1004 
1005 	cache_bucket_load(&cache->uc_freebucket, b);
1006 }
1007 
1008 #ifdef NUMA
1009 static inline void
1010 cache_bucket_load_cross(uma_cache_t cache, uma_bucket_t b)
1011 {
1012 
1013 	cache_bucket_load(&cache->uc_crossbucket, b);
1014 }
1015 #endif
1016 
1017 /*
1018  * Copy and preserve ucb_spare.
1019  */
1020 static inline void
1021 cache_bucket_copy(uma_cache_bucket_t b1, uma_cache_bucket_t b2)
1022 {
1023 
1024 	b1->ucb_bucket = b2->ucb_bucket;
1025 	b1->ucb_entries = b2->ucb_entries;
1026 	b1->ucb_cnt = b2->ucb_cnt;
1027 }
1028 
1029 /*
1030  * Swap two cache buckets.
1031  */
1032 static inline void
1033 cache_bucket_swap(uma_cache_bucket_t b1, uma_cache_bucket_t b2)
1034 {
1035 	struct uma_cache_bucket b3;
1036 
1037 	CRITICAL_ASSERT(curthread);
1038 
1039 	cache_bucket_copy(&b3, b1);
1040 	cache_bucket_copy(b1, b2);
1041 	cache_bucket_copy(b2, &b3);
1042 }
1043 
1044 /*
1045  * Attempt to fetch a bucket from a zone on behalf of the current cpu cache.
1046  */
1047 static uma_bucket_t
1048 cache_fetch_bucket(uma_zone_t zone, uma_cache_t cache, int domain)
1049 {
1050 	uma_zone_domain_t zdom;
1051 	uma_bucket_t bucket;
1052 	smr_seq_t seq;
1053 
1054 	/*
1055 	 * Avoid the lock if possible.
1056 	 */
1057 	zdom = ZDOM_GET(zone, domain);
1058 	if (zdom->uzd_nitems == 0)
1059 		return (NULL);
1060 
1061 	if ((cache_uz_flags(cache) & UMA_ZONE_SMR) != 0 &&
1062 	    (seq = atomic_load_32(&zdom->uzd_seq)) != SMR_SEQ_INVALID &&
1063 	    !smr_poll(zone->uz_smr, seq, false))
1064 		return (NULL);
1065 
1066 	/*
1067 	 * Check the zone's cache of buckets.
1068 	 */
1069 	zdom = zone_domain_lock(zone, domain);
1070 	if ((bucket = zone_fetch_bucket(zone, zdom, false)) != NULL)
1071 		return (bucket);
1072 	ZDOM_UNLOCK(zdom);
1073 
1074 	return (NULL);
1075 }
1076 
1077 static void
1078 zone_log_warning(uma_zone_t zone)
1079 {
1080 	static const struct timeval warninterval = { 300, 0 };
1081 
1082 	if (!zone_warnings || zone->uz_warning == NULL)
1083 		return;
1084 
1085 	if (ratecheck(&zone->uz_ratecheck, &warninterval))
1086 		printf("[zone: %s] %s\n", zone->uz_name, zone->uz_warning);
1087 }
1088 
1089 static inline void
1090 zone_maxaction(uma_zone_t zone)
1091 {
1092 
1093 	if (zone->uz_maxaction.ta_func != NULL)
1094 		taskqueue_enqueue(taskqueue_thread, &zone->uz_maxaction);
1095 }
1096 
1097 /*
1098  * Routine called by timeout which is used to fire off some time interval
1099  * based calculations.  (stats, hash size, etc.)
1100  *
1101  * Arguments:
1102  *	arg   Unused
1103  *
1104  * Returns:
1105  *	Nothing
1106  */
1107 static void
1108 uma_timeout(void *context __unused, int pending __unused)
1109 {
1110 	bucket_enable();
1111 	zone_foreach(zone_timeout, NULL);
1112 
1113 	/* Reschedule this event */
1114 	taskqueue_enqueue_timeout(taskqueue_thread, &uma_timeout_task,
1115 	    UMA_TIMEOUT * hz);
1116 }
1117 
1118 /*
1119  * Update the working set size estimates for the zone's bucket cache.
1120  * The constants chosen here are somewhat arbitrary.
1121  */
1122 static void
1123 zone_domain_update_wss(uma_zone_domain_t zdom)
1124 {
1125 	long m;
1126 
1127 	ZDOM_LOCK_ASSERT(zdom);
1128 	MPASS(zdom->uzd_imax >= zdom->uzd_nitems);
1129 	MPASS(zdom->uzd_nitems >= zdom->uzd_bimin);
1130 	MPASS(zdom->uzd_bimin >= zdom->uzd_imin);
1131 
1132 	/*
1133 	 * Estimate WSS as modified moving average of biggest allocation
1134 	 * batches for each period over few minutes (UMA_TIMEOUT of 20s).
1135 	 */
1136 	zdom->uzd_wss = lmax(zdom->uzd_wss * 3 / 4,
1137 	    zdom->uzd_imax - zdom->uzd_bimin);
1138 
1139 	/*
1140 	 * Estimate longtime minimum item count as a combination of recent
1141 	 * minimum item count, adjusted by WSS for safety, and the modified
1142 	 * moving average over the last several hours (UMA_TIMEOUT of 20s).
1143 	 * timin measures time since limin tried to go negative, that means
1144 	 * we were dangerously close to or got out of cache.
1145 	 */
1146 	m = zdom->uzd_imin - zdom->uzd_wss;
1147 	if (m >= 0) {
1148 		if (zdom->uzd_limin >= m)
1149 			zdom->uzd_limin = m;
1150 		else
1151 			zdom->uzd_limin = (m + zdom->uzd_limin * 255) / 256;
1152 		zdom->uzd_timin++;
1153 	} else {
1154 		zdom->uzd_limin = 0;
1155 		zdom->uzd_timin = 0;
1156 	}
1157 
1158 	/* To reduce period edge effects on WSS keep half of the imax. */
1159 	atomic_subtract_long(&zdom->uzd_imax,
1160 	    (zdom->uzd_imax - zdom->uzd_nitems + 1) / 2);
1161 	zdom->uzd_imin = zdom->uzd_bimin = zdom->uzd_nitems;
1162 }
1163 
1164 /*
1165  * Routine to perform timeout driven calculations.  This expands the
1166  * hashes and does per cpu statistics aggregation.
1167  *
1168  *  Returns nothing.
1169  */
1170 static void
1171 zone_timeout(uma_zone_t zone, void *unused)
1172 {
1173 	uma_keg_t keg;
1174 	u_int slabs, pages;
1175 
1176 	if ((zone->uz_flags & UMA_ZFLAG_HASH) == 0)
1177 		goto trim;
1178 
1179 	keg = zone->uz_keg;
1180 
1181 	/*
1182 	 * Hash zones are non-numa by definition so the first domain
1183 	 * is the only one present.
1184 	 */
1185 	KEG_LOCK(keg, 0);
1186 	pages = keg->uk_domain[0].ud_pages;
1187 
1188 	/*
1189 	 * Expand the keg hash table.
1190 	 *
1191 	 * This is done if the number of slabs is larger than the hash size.
1192 	 * What I'm trying to do here is completely reduce collisions.  This
1193 	 * may be a little aggressive.  Should I allow for two collisions max?
1194 	 */
1195 	if ((slabs = pages / keg->uk_ppera) > keg->uk_hash.uh_hashsize) {
1196 		struct uma_hash newhash;
1197 		struct uma_hash oldhash;
1198 		int ret;
1199 
1200 		/*
1201 		 * This is so involved because allocating and freeing
1202 		 * while the keg lock is held will lead to deadlock.
1203 		 * I have to do everything in stages and check for
1204 		 * races.
1205 		 */
1206 		KEG_UNLOCK(keg, 0);
1207 		ret = hash_alloc(&newhash, 1 << fls(slabs));
1208 		KEG_LOCK(keg, 0);
1209 		if (ret) {
1210 			if (hash_expand(&keg->uk_hash, &newhash)) {
1211 				oldhash = keg->uk_hash;
1212 				keg->uk_hash = newhash;
1213 			} else
1214 				oldhash = newhash;
1215 
1216 			KEG_UNLOCK(keg, 0);
1217 			hash_free(&oldhash);
1218 			goto trim;
1219 		}
1220 	}
1221 	KEG_UNLOCK(keg, 0);
1222 
1223 trim:
1224 	/* Trim caches not used for a long time. */
1225 	if ((zone->uz_flags & UMA_ZONE_UNMANAGED) == 0) {
1226 		for (int i = 0; i < vm_ndomains; i++) {
1227 			if (bucket_cache_reclaim_domain(zone, false, false, i) &&
1228 			    (zone->uz_flags & UMA_ZFLAG_CACHE) == 0)
1229 				keg_drain(zone->uz_keg, i);
1230 		}
1231 	}
1232 }
1233 
1234 /*
1235  * Allocate and zero fill the next sized hash table from the appropriate
1236  * backing store.
1237  *
1238  * Arguments:
1239  *	hash  A new hash structure with the old hash size in uh_hashsize
1240  *
1241  * Returns:
1242  *	1 on success and 0 on failure.
1243  */
1244 static int
1245 hash_alloc(struct uma_hash *hash, u_int size)
1246 {
1247 	size_t alloc;
1248 
1249 	KASSERT(powerof2(size), ("hash size must be power of 2"));
1250 	if (size > UMA_HASH_SIZE_INIT)  {
1251 		hash->uh_hashsize = size;
1252 		alloc = sizeof(hash->uh_slab_hash[0]) * hash->uh_hashsize;
1253 		hash->uh_slab_hash = malloc(alloc, M_UMAHASH, M_NOWAIT);
1254 	} else {
1255 		alloc = sizeof(hash->uh_slab_hash[0]) * UMA_HASH_SIZE_INIT;
1256 		hash->uh_slab_hash = zone_alloc_item(hashzone, NULL,
1257 		    UMA_ANYDOMAIN, M_WAITOK);
1258 		hash->uh_hashsize = UMA_HASH_SIZE_INIT;
1259 	}
1260 	if (hash->uh_slab_hash) {
1261 		bzero(hash->uh_slab_hash, alloc);
1262 		hash->uh_hashmask = hash->uh_hashsize - 1;
1263 		return (1);
1264 	}
1265 
1266 	return (0);
1267 }
1268 
1269 /*
1270  * Expands the hash table for HASH zones.  This is done from zone_timeout
1271  * to reduce collisions.  This must not be done in the regular allocation
1272  * path, otherwise, we can recurse on the vm while allocating pages.
1273  *
1274  * Arguments:
1275  *	oldhash  The hash you want to expand
1276  *	newhash  The hash structure for the new table
1277  *
1278  * Returns:
1279  *	Nothing
1280  *
1281  * Discussion:
1282  */
1283 static int
1284 hash_expand(struct uma_hash *oldhash, struct uma_hash *newhash)
1285 {
1286 	uma_hash_slab_t slab;
1287 	u_int hval;
1288 	u_int idx;
1289 
1290 	if (!newhash->uh_slab_hash)
1291 		return (0);
1292 
1293 	if (oldhash->uh_hashsize >= newhash->uh_hashsize)
1294 		return (0);
1295 
1296 	/*
1297 	 * I need to investigate hash algorithms for resizing without a
1298 	 * full rehash.
1299 	 */
1300 
1301 	for (idx = 0; idx < oldhash->uh_hashsize; idx++)
1302 		while (!LIST_EMPTY(&oldhash->uh_slab_hash[idx])) {
1303 			slab = LIST_FIRST(&oldhash->uh_slab_hash[idx]);
1304 			LIST_REMOVE(slab, uhs_hlink);
1305 			hval = UMA_HASH(newhash, slab->uhs_data);
1306 			LIST_INSERT_HEAD(&newhash->uh_slab_hash[hval],
1307 			    slab, uhs_hlink);
1308 		}
1309 
1310 	return (1);
1311 }
1312 
1313 /*
1314  * Free the hash bucket to the appropriate backing store.
1315  *
1316  * Arguments:
1317  *	slab_hash  The hash bucket we're freeing
1318  *	hashsize   The number of entries in that hash bucket
1319  *
1320  * Returns:
1321  *	Nothing
1322  */
1323 static void
1324 hash_free(struct uma_hash *hash)
1325 {
1326 	if (hash->uh_slab_hash == NULL)
1327 		return;
1328 	if (hash->uh_hashsize == UMA_HASH_SIZE_INIT)
1329 		zone_free_item(hashzone, hash->uh_slab_hash, NULL, SKIP_NONE);
1330 	else
1331 		free(hash->uh_slab_hash, M_UMAHASH);
1332 }
1333 
1334 /*
1335  * Frees all outstanding items in a bucket
1336  *
1337  * Arguments:
1338  *	zone   The zone to free to, must be unlocked.
1339  *	bucket The free/alloc bucket with items.
1340  *
1341  * Returns:
1342  *	Nothing
1343  */
1344 static void
1345 bucket_drain(uma_zone_t zone, uma_bucket_t bucket)
1346 {
1347 	int i;
1348 
1349 	if (bucket->ub_cnt == 0)
1350 		return;
1351 
1352 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0 &&
1353 	    bucket->ub_seq != SMR_SEQ_INVALID) {
1354 		smr_wait(zone->uz_smr, bucket->ub_seq);
1355 		bucket->ub_seq = SMR_SEQ_INVALID;
1356 		for (i = 0; i < bucket->ub_cnt; i++)
1357 			item_dtor(zone, bucket->ub_bucket[i],
1358 			    zone->uz_size, NULL, SKIP_NONE);
1359 	}
1360 	if (zone->uz_fini)
1361 		for (i = 0; i < bucket->ub_cnt; i++) {
1362 			kasan_mark_item_valid(zone, bucket->ub_bucket[i]);
1363 			zone->uz_fini(bucket->ub_bucket[i], zone->uz_size);
1364 			kasan_mark_item_invalid(zone, bucket->ub_bucket[i]);
1365 		}
1366 	zone->uz_release(zone->uz_arg, bucket->ub_bucket, bucket->ub_cnt);
1367 	if (zone->uz_max_items > 0)
1368 		zone_free_limit(zone, bucket->ub_cnt);
1369 #ifdef INVARIANTS
1370 	bzero(bucket->ub_bucket, sizeof(void *) * bucket->ub_cnt);
1371 #endif
1372 	bucket->ub_cnt = 0;
1373 }
1374 
1375 /*
1376  * Drains the per cpu caches for a zone.
1377  *
1378  * NOTE: This may only be called while the zone is being torn down, and not
1379  * during normal operation.  This is necessary in order that we do not have
1380  * to migrate CPUs to drain the per-CPU caches.
1381  *
1382  * Arguments:
1383  *	zone     The zone to drain, must be unlocked.
1384  *
1385  * Returns:
1386  *	Nothing
1387  */
1388 static void
1389 cache_drain(uma_zone_t zone)
1390 {
1391 	uma_cache_t cache;
1392 	uma_bucket_t bucket;
1393 	smr_seq_t seq;
1394 	int cpu;
1395 
1396 	/*
1397 	 * XXX: It is safe to not lock the per-CPU caches, because we're
1398 	 * tearing down the zone anyway.  I.e., there will be no further use
1399 	 * of the caches at this point.
1400 	 *
1401 	 * XXX: It would good to be able to assert that the zone is being
1402 	 * torn down to prevent improper use of cache_drain().
1403 	 */
1404 	seq = SMR_SEQ_INVALID;
1405 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
1406 		seq = smr_advance(zone->uz_smr);
1407 	CPU_FOREACH(cpu) {
1408 		cache = &zone->uz_cpu[cpu];
1409 		bucket = cache_bucket_unload_alloc(cache);
1410 		if (bucket != NULL)
1411 			bucket_free(zone, bucket, NULL);
1412 		bucket = cache_bucket_unload_free(cache);
1413 		if (bucket != NULL) {
1414 			bucket->ub_seq = seq;
1415 			bucket_free(zone, bucket, NULL);
1416 		}
1417 		bucket = cache_bucket_unload_cross(cache);
1418 		if (bucket != NULL) {
1419 			bucket->ub_seq = seq;
1420 			bucket_free(zone, bucket, NULL);
1421 		}
1422 	}
1423 	bucket_cache_reclaim(zone, true, UMA_ANYDOMAIN);
1424 }
1425 
1426 static void
1427 cache_shrink(uma_zone_t zone, void *unused)
1428 {
1429 
1430 	if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
1431 		return;
1432 
1433 	ZONE_LOCK(zone);
1434 	zone->uz_bucket_size =
1435 	    (zone->uz_bucket_size_min + zone->uz_bucket_size) / 2;
1436 	ZONE_UNLOCK(zone);
1437 }
1438 
1439 static void
1440 cache_drain_safe_cpu(uma_zone_t zone, void *unused)
1441 {
1442 	uma_cache_t cache;
1443 	uma_bucket_t b1, b2, b3;
1444 	int domain;
1445 
1446 	if (zone->uz_flags & UMA_ZFLAG_INTERNAL)
1447 		return;
1448 
1449 	b1 = b2 = b3 = NULL;
1450 	critical_enter();
1451 	cache = &zone->uz_cpu[curcpu];
1452 	domain = PCPU_GET(domain);
1453 	b1 = cache_bucket_unload_alloc(cache);
1454 
1455 	/*
1456 	 * Don't flush SMR zone buckets.  This leaves the zone without a
1457 	 * bucket and forces every free to synchronize().
1458 	 */
1459 	if ((zone->uz_flags & UMA_ZONE_SMR) == 0) {
1460 		b2 = cache_bucket_unload_free(cache);
1461 		b3 = cache_bucket_unload_cross(cache);
1462 	}
1463 	critical_exit();
1464 
1465 	if (b1 != NULL)
1466 		zone_free_bucket(zone, b1, NULL, domain, false);
1467 	if (b2 != NULL)
1468 		zone_free_bucket(zone, b2, NULL, domain, false);
1469 	if (b3 != NULL) {
1470 		/* Adjust the domain so it goes to zone_free_cross. */
1471 		domain = (domain + 1) % vm_ndomains;
1472 		zone_free_bucket(zone, b3, NULL, domain, false);
1473 	}
1474 }
1475 
1476 /*
1477  * Safely drain per-CPU caches of a zone(s) to alloc bucket.
1478  * This is an expensive call because it needs to bind to all CPUs
1479  * one by one and enter a critical section on each of them in order
1480  * to safely access their cache buckets.
1481  * Zone lock must not be held on call this function.
1482  */
1483 static void
1484 pcpu_cache_drain_safe(uma_zone_t zone)
1485 {
1486 	int cpu;
1487 
1488 	/*
1489 	 * Polite bucket sizes shrinking was not enough, shrink aggressively.
1490 	 */
1491 	if (zone)
1492 		cache_shrink(zone, NULL);
1493 	else
1494 		zone_foreach(cache_shrink, NULL);
1495 
1496 	CPU_FOREACH(cpu) {
1497 		thread_lock(curthread);
1498 		sched_bind(curthread, cpu);
1499 		thread_unlock(curthread);
1500 
1501 		if (zone)
1502 			cache_drain_safe_cpu(zone, NULL);
1503 		else
1504 			zone_foreach(cache_drain_safe_cpu, NULL);
1505 	}
1506 	thread_lock(curthread);
1507 	sched_unbind(curthread);
1508 	thread_unlock(curthread);
1509 }
1510 
1511 /*
1512  * Reclaim cached buckets from a zone.  All buckets are reclaimed if the caller
1513  * requested a drain, otherwise the per-domain caches are trimmed to either
1514  * estimated working set size.
1515  */
1516 static bool
1517 bucket_cache_reclaim_domain(uma_zone_t zone, bool drain, bool trim, int domain)
1518 {
1519 	uma_zone_domain_t zdom;
1520 	uma_bucket_t bucket;
1521 	long target;
1522 	bool done = false;
1523 
1524 	/*
1525 	 * The cross bucket is partially filled and not part of
1526 	 * the item count.  Reclaim it individually here.
1527 	 */
1528 	zdom = ZDOM_GET(zone, domain);
1529 	if ((zone->uz_flags & UMA_ZONE_SMR) == 0 || drain) {
1530 		ZONE_CROSS_LOCK(zone);
1531 		bucket = zdom->uzd_cross;
1532 		zdom->uzd_cross = NULL;
1533 		ZONE_CROSS_UNLOCK(zone);
1534 		if (bucket != NULL)
1535 			bucket_free(zone, bucket, NULL);
1536 	}
1537 
1538 	/*
1539 	 * If we were asked to drain the zone, we are done only once
1540 	 * this bucket cache is empty.  If trim, we reclaim items in
1541 	 * excess of the zone's estimated working set size.  Multiple
1542 	 * consecutive calls will shrink the WSS and so reclaim more.
1543 	 * If neither drain nor trim, then voluntarily reclaim 1/4
1544 	 * (to reduce first spike) of items not used for a long time.
1545 	 */
1546 	ZDOM_LOCK(zdom);
1547 	zone_domain_update_wss(zdom);
1548 	if (drain)
1549 		target = 0;
1550 	else if (trim)
1551 		target = zdom->uzd_wss;
1552 	else if (zdom->uzd_timin > 900 / UMA_TIMEOUT)
1553 		target = zdom->uzd_nitems - zdom->uzd_limin / 4;
1554 	else {
1555 		ZDOM_UNLOCK(zdom);
1556 		return (done);
1557 	}
1558 	while ((bucket = STAILQ_FIRST(&zdom->uzd_buckets)) != NULL &&
1559 	    zdom->uzd_nitems >= target + bucket->ub_cnt) {
1560 		bucket = zone_fetch_bucket(zone, zdom, true);
1561 		if (bucket == NULL)
1562 			break;
1563 		bucket_free(zone, bucket, NULL);
1564 		done = true;
1565 		ZDOM_LOCK(zdom);
1566 	}
1567 	ZDOM_UNLOCK(zdom);
1568 	return (done);
1569 }
1570 
1571 static void
1572 bucket_cache_reclaim(uma_zone_t zone, bool drain, int domain)
1573 {
1574 	int i;
1575 
1576 	/*
1577 	 * Shrink the zone bucket size to ensure that the per-CPU caches
1578 	 * don't grow too large.
1579 	 */
1580 	if (zone->uz_bucket_size > zone->uz_bucket_size_min)
1581 		zone->uz_bucket_size--;
1582 
1583 	if (domain != UMA_ANYDOMAIN &&
1584 	    (zone->uz_flags & UMA_ZONE_ROUNDROBIN) == 0) {
1585 		bucket_cache_reclaim_domain(zone, drain, true, domain);
1586 	} else {
1587 		for (i = 0; i < vm_ndomains; i++)
1588 			bucket_cache_reclaim_domain(zone, drain, true, i);
1589 	}
1590 }
1591 
1592 static void
1593 keg_free_slab(uma_keg_t keg, uma_slab_t slab, int start)
1594 {
1595 	uint8_t *mem;
1596 	size_t size;
1597 	int i;
1598 	uint8_t flags;
1599 
1600 	CTR4(KTR_UMA, "keg_free_slab keg %s(%p) slab %p, returning %d bytes",
1601 	    keg->uk_name, keg, slab, PAGE_SIZE * keg->uk_ppera);
1602 
1603 	mem = slab_data(slab, keg);
1604 	size = PAGE_SIZE * keg->uk_ppera;
1605 
1606 	kasan_mark_slab_valid(keg, mem);
1607 	if (keg->uk_fini != NULL) {
1608 		for (i = start - 1; i > -1; i--)
1609 #ifdef INVARIANTS
1610 		/*
1611 		 * trash_fini implies that dtor was trash_dtor. trash_fini
1612 		 * would check that memory hasn't been modified since free,
1613 		 * which executed trash_dtor.
1614 		 * That's why we need to run uma_dbg_kskip() check here,
1615 		 * albeit we don't make skip check for other init/fini
1616 		 * invocations.
1617 		 */
1618 		if (!uma_dbg_kskip(keg, slab_item(slab, keg, i)) ||
1619 		    keg->uk_fini != trash_fini)
1620 #endif
1621 			keg->uk_fini(slab_item(slab, keg, i), keg->uk_size);
1622 	}
1623 	flags = slab->us_flags;
1624 	if (keg->uk_flags & UMA_ZFLAG_OFFPAGE) {
1625 		zone_free_item(slabzone(keg->uk_ipers), slab_tohashslab(slab),
1626 		    NULL, SKIP_NONE);
1627 	}
1628 	keg->uk_freef(mem, size, flags);
1629 	uma_total_dec(size);
1630 }
1631 
1632 static void
1633 keg_drain_domain(uma_keg_t keg, int domain)
1634 {
1635 	struct slabhead freeslabs;
1636 	uma_domain_t dom;
1637 	uma_slab_t slab, tmp;
1638 	uint32_t i, stofree, stokeep, partial;
1639 
1640 	dom = &keg->uk_domain[domain];
1641 	LIST_INIT(&freeslabs);
1642 
1643 	CTR4(KTR_UMA, "keg_drain %s(%p) domain %d free items: %u",
1644 	    keg->uk_name, keg, domain, dom->ud_free_items);
1645 
1646 	KEG_LOCK(keg, domain);
1647 
1648 	/*
1649 	 * Are the free items in partially allocated slabs sufficient to meet
1650 	 * the reserve? If not, compute the number of fully free slabs that must
1651 	 * be kept.
1652 	 */
1653 	partial = dom->ud_free_items - dom->ud_free_slabs * keg->uk_ipers;
1654 	if (partial < keg->uk_reserve) {
1655 		stokeep = min(dom->ud_free_slabs,
1656 		    howmany(keg->uk_reserve - partial, keg->uk_ipers));
1657 	} else {
1658 		stokeep = 0;
1659 	}
1660 	stofree = dom->ud_free_slabs - stokeep;
1661 
1662 	/*
1663 	 * Partition the free slabs into two sets: those that must be kept in
1664 	 * order to maintain the reserve, and those that may be released back to
1665 	 * the system.  Since one set may be much larger than the other,
1666 	 * populate the smaller of the two sets and swap them if necessary.
1667 	 */
1668 	for (i = min(stofree, stokeep); i > 0; i--) {
1669 		slab = LIST_FIRST(&dom->ud_free_slab);
1670 		LIST_REMOVE(slab, us_link);
1671 		LIST_INSERT_HEAD(&freeslabs, slab, us_link);
1672 	}
1673 	if (stofree > stokeep)
1674 		LIST_SWAP(&freeslabs, &dom->ud_free_slab, uma_slab, us_link);
1675 
1676 	if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0) {
1677 		LIST_FOREACH(slab, &freeslabs, us_link)
1678 			UMA_HASH_REMOVE(&keg->uk_hash, slab);
1679 	}
1680 	dom->ud_free_items -= stofree * keg->uk_ipers;
1681 	dom->ud_free_slabs -= stofree;
1682 	dom->ud_pages -= stofree * keg->uk_ppera;
1683 	KEG_UNLOCK(keg, domain);
1684 
1685 	LIST_FOREACH_SAFE(slab, &freeslabs, us_link, tmp)
1686 		keg_free_slab(keg, slab, keg->uk_ipers);
1687 }
1688 
1689 /*
1690  * Frees pages from a keg back to the system.  This is done on demand from
1691  * the pageout daemon.
1692  *
1693  * Returns nothing.
1694  */
1695 static void
1696 keg_drain(uma_keg_t keg, int domain)
1697 {
1698 	int i;
1699 
1700 	if ((keg->uk_flags & UMA_ZONE_NOFREE) != 0)
1701 		return;
1702 	if (domain != UMA_ANYDOMAIN) {
1703 		keg_drain_domain(keg, domain);
1704 	} else {
1705 		for (i = 0; i < vm_ndomains; i++)
1706 			keg_drain_domain(keg, i);
1707 	}
1708 }
1709 
1710 static void
1711 zone_reclaim(uma_zone_t zone, int domain, int waitok, bool drain)
1712 {
1713 	/*
1714 	 * Count active reclaim operations in order to interlock with
1715 	 * zone_dtor(), which removes the zone from global lists before
1716 	 * attempting to reclaim items itself.
1717 	 *
1718 	 * The zone may be destroyed while sleeping, so only zone_dtor() should
1719 	 * specify M_WAITOK.
1720 	 */
1721 	ZONE_LOCK(zone);
1722 	if (waitok == M_WAITOK) {
1723 		while (zone->uz_reclaimers > 0)
1724 			msleep(zone, ZONE_LOCKPTR(zone), PVM, "zonedrain", 1);
1725 	}
1726 	zone->uz_reclaimers++;
1727 	ZONE_UNLOCK(zone);
1728 	bucket_cache_reclaim(zone, drain, domain);
1729 
1730 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) == 0)
1731 		keg_drain(zone->uz_keg, domain);
1732 	ZONE_LOCK(zone);
1733 	zone->uz_reclaimers--;
1734 	if (zone->uz_reclaimers == 0)
1735 		wakeup(zone);
1736 	ZONE_UNLOCK(zone);
1737 }
1738 
1739 /*
1740  * Allocate a new slab for a keg and inserts it into the partial slab list.
1741  * The keg should be unlocked on entry.  If the allocation succeeds it will
1742  * be locked on return.
1743  *
1744  * Arguments:
1745  *	flags   Wait flags for the item initialization routine
1746  *	aflags  Wait flags for the slab allocation
1747  *
1748  * Returns:
1749  *	The slab that was allocated or NULL if there is no memory and the
1750  *	caller specified M_NOWAIT.
1751  */
1752 static uma_slab_t
1753 keg_alloc_slab(uma_keg_t keg, uma_zone_t zone, int domain, int flags,
1754     int aflags)
1755 {
1756 	uma_domain_t dom;
1757 	uma_slab_t slab;
1758 	unsigned long size;
1759 	uint8_t *mem;
1760 	uint8_t sflags;
1761 	int i;
1762 
1763 	TSENTER();
1764 
1765 	KASSERT(domain >= 0 && domain < vm_ndomains,
1766 	    ("keg_alloc_slab: domain %d out of range", domain));
1767 
1768 	slab = NULL;
1769 	mem = NULL;
1770 	if (keg->uk_flags & UMA_ZFLAG_OFFPAGE) {
1771 		uma_hash_slab_t hslab;
1772 		hslab = zone_alloc_item(slabzone(keg->uk_ipers), NULL,
1773 		    domain, aflags);
1774 		if (hslab == NULL)
1775 			goto fail;
1776 		slab = &hslab->uhs_slab;
1777 	}
1778 
1779 	/*
1780 	 * This reproduces the old vm_zone behavior of zero filling pages the
1781 	 * first time they are added to a zone.
1782 	 *
1783 	 * Malloced items are zeroed in uma_zalloc.
1784 	 */
1785 
1786 	if ((keg->uk_flags & UMA_ZONE_MALLOC) == 0)
1787 		aflags |= M_ZERO;
1788 	else
1789 		aflags &= ~M_ZERO;
1790 
1791 	if (keg->uk_flags & UMA_ZONE_NODUMP)
1792 		aflags |= M_NODUMP;
1793 
1794 	if (keg->uk_flags & UMA_ZONE_NOFREE)
1795 		aflags |= M_NEVERFREED;
1796 
1797 	/* zone is passed for legacy reasons. */
1798 	size = keg->uk_ppera * PAGE_SIZE;
1799 	mem = keg->uk_allocf(zone, size, domain, &sflags, aflags);
1800 	if (mem == NULL) {
1801 		if (keg->uk_flags & UMA_ZFLAG_OFFPAGE)
1802 			zone_free_item(slabzone(keg->uk_ipers),
1803 			    slab_tohashslab(slab), NULL, SKIP_NONE);
1804 		goto fail;
1805 	}
1806 	uma_total_inc(size);
1807 
1808 	/* For HASH zones all pages go to the same uma_domain. */
1809 	if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0)
1810 		domain = 0;
1811 
1812 	kmsan_mark(mem, size,
1813 	    (aflags & M_ZERO) != 0 ? KMSAN_STATE_INITED : KMSAN_STATE_UNINIT);
1814 
1815 	/* Point the slab into the allocated memory */
1816 	if (!(keg->uk_flags & UMA_ZFLAG_OFFPAGE))
1817 		slab = (uma_slab_t)(mem + keg->uk_pgoff);
1818 	else
1819 		slab_tohashslab(slab)->uhs_data = mem;
1820 
1821 	if (keg->uk_flags & UMA_ZFLAG_VTOSLAB)
1822 		for (i = 0; i < keg->uk_ppera; i++)
1823 			vsetzoneslab((vm_offset_t)mem + (i * PAGE_SIZE),
1824 			    zone, slab);
1825 
1826 	slab->us_freecount = keg->uk_ipers;
1827 	slab->us_flags = sflags;
1828 	slab->us_domain = domain;
1829 
1830 	BIT_FILL(keg->uk_ipers, &slab->us_free);
1831 #ifdef INVARIANTS
1832 	BIT_ZERO(keg->uk_ipers, slab_dbg_bits(slab, keg));
1833 #endif
1834 
1835 	if (keg->uk_init != NULL) {
1836 		for (i = 0; i < keg->uk_ipers; i++)
1837 			if (keg->uk_init(slab_item(slab, keg, i),
1838 			    keg->uk_size, flags) != 0)
1839 				break;
1840 		if (i != keg->uk_ipers) {
1841 			keg_free_slab(keg, slab, i);
1842 			goto fail;
1843 		}
1844 	}
1845 	kasan_mark_slab_invalid(keg, mem);
1846 	KEG_LOCK(keg, domain);
1847 
1848 	CTR3(KTR_UMA, "keg_alloc_slab: allocated slab %p for %s(%p)",
1849 	    slab, keg->uk_name, keg);
1850 
1851 	if (keg->uk_flags & UMA_ZFLAG_HASH)
1852 		UMA_HASH_INSERT(&keg->uk_hash, slab, mem);
1853 
1854 	/*
1855 	 * If we got a slab here it's safe to mark it partially used
1856 	 * and return.  We assume that the caller is going to remove
1857 	 * at least one item.
1858 	 */
1859 	dom = &keg->uk_domain[domain];
1860 	LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
1861 	dom->ud_pages += keg->uk_ppera;
1862 	dom->ud_free_items += keg->uk_ipers;
1863 
1864 	TSEXIT();
1865 	return (slab);
1866 
1867 fail:
1868 	return (NULL);
1869 }
1870 
1871 /*
1872  * This function is intended to be used early on in place of page_alloc().  It
1873  * performs contiguous physical memory allocations and uses a bump allocator for
1874  * KVA, so is usable before the kernel map is initialized.
1875  */
1876 static void *
1877 startup_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1878     int wait)
1879 {
1880 	vm_paddr_t pa;
1881 	vm_page_t m;
1882 	int i, pages;
1883 
1884 	pages = howmany(bytes, PAGE_SIZE);
1885 	KASSERT(pages > 0, ("%s can't reserve 0 pages", __func__));
1886 
1887 	*pflag = UMA_SLAB_BOOT;
1888 	m = vm_page_alloc_noobj_contig_domain(domain, malloc2vm_flags(wait) |
1889 	    VM_ALLOC_WIRED, pages, (vm_paddr_t)0, ~(vm_paddr_t)0, 1, 0,
1890 	    VM_MEMATTR_DEFAULT);
1891 	if (m == NULL)
1892 		return (NULL);
1893 
1894 	pa = VM_PAGE_TO_PHYS(m);
1895 	for (i = 0; i < pages; i++, pa += PAGE_SIZE) {
1896 #if MINIDUMP_PAGE_TRACKING && MINIDUMP_STARTUP_PAGE_TRACKING
1897 		if ((wait & M_NODUMP) == 0)
1898 			dump_add_page(pa);
1899 #endif
1900 	}
1901 
1902 	/* Allocate KVA and indirectly advance bootmem. */
1903 	return ((void *)pmap_map(&bootmem, m->phys_addr,
1904 	    m->phys_addr + (pages * PAGE_SIZE), VM_PROT_READ | VM_PROT_WRITE));
1905 }
1906 
1907 static void
1908 startup_free(void *mem, vm_size_t bytes)
1909 {
1910 	vm_offset_t va;
1911 	vm_page_t m;
1912 
1913 	va = (vm_offset_t)mem;
1914 	m = PHYS_TO_VM_PAGE(pmap_kextract(va));
1915 
1916 	/*
1917 	 * startup_alloc() returns direct-mapped slabs on some platforms.  Avoid
1918 	 * unmapping ranges of the direct map.
1919 	 */
1920 	if (va >= bootstart && va + bytes <= bootmem)
1921 		pmap_remove(kernel_pmap, va, va + bytes);
1922 	for (; bytes != 0; bytes -= PAGE_SIZE, m++) {
1923 #if MINIDUMP_PAGE_TRACKING && MINIDUMP_STARTUP_PAGE_TRACKING
1924 		dump_drop_page(VM_PAGE_TO_PHYS(m));
1925 #endif
1926 		vm_page_unwire_noq(m);
1927 		vm_page_free(m);
1928 	}
1929 }
1930 
1931 /*
1932  * Allocates a number of pages from the system
1933  *
1934  * Arguments:
1935  *	bytes  The number of bytes requested
1936  *	wait  Shall we wait?
1937  *
1938  * Returns:
1939  *	A pointer to the alloced memory or possibly
1940  *	NULL if M_NOWAIT is set.
1941  */
1942 static void *
1943 page_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1944     int wait)
1945 {
1946 	void *p;	/* Returned page */
1947 
1948 	*pflag = UMA_SLAB_KERNEL;
1949 	p = kmem_malloc_domainset(DOMAINSET_FIXED(domain), bytes, wait);
1950 
1951 	return (p);
1952 }
1953 
1954 static void *
1955 pcpu_page_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
1956     int wait)
1957 {
1958 	struct pglist alloctail;
1959 	vm_offset_t addr, zkva;
1960 	int cpu, flags;
1961 	vm_page_t p, p_next;
1962 #ifdef NUMA
1963 	struct pcpu *pc;
1964 #endif
1965 
1966 	MPASS(bytes == (mp_maxid + 1) * PAGE_SIZE);
1967 
1968 	TAILQ_INIT(&alloctail);
1969 	flags = VM_ALLOC_SYSTEM | VM_ALLOC_WIRED | malloc2vm_flags(wait);
1970 	*pflag = UMA_SLAB_KERNEL;
1971 	for (cpu = 0; cpu <= mp_maxid; cpu++) {
1972 		if (CPU_ABSENT(cpu)) {
1973 			p = vm_page_alloc_noobj(flags);
1974 		} else {
1975 #ifndef NUMA
1976 			p = vm_page_alloc_noobj(flags);
1977 #else
1978 			pc = pcpu_find(cpu);
1979 			if (__predict_false(VM_DOMAIN_EMPTY(pc->pc_domain)))
1980 				p = NULL;
1981 			else
1982 				p = vm_page_alloc_noobj_domain(pc->pc_domain,
1983 				    flags);
1984 			if (__predict_false(p == NULL))
1985 				p = vm_page_alloc_noobj(flags);
1986 #endif
1987 		}
1988 		if (__predict_false(p == NULL))
1989 			goto fail;
1990 		TAILQ_INSERT_TAIL(&alloctail, p, listq);
1991 	}
1992 	if ((addr = kva_alloc(bytes)) == 0)
1993 		goto fail;
1994 	zkva = addr;
1995 	TAILQ_FOREACH(p, &alloctail, listq) {
1996 		pmap_qenter(zkva, &p, 1);
1997 		zkva += PAGE_SIZE;
1998 	}
1999 	return ((void*)addr);
2000 fail:
2001 	TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
2002 		vm_page_unwire_noq(p);
2003 		vm_page_free(p);
2004 	}
2005 	return (NULL);
2006 }
2007 
2008 /*
2009  * Allocates a number of pages not belonging to a VM object
2010  *
2011  * Arguments:
2012  *	bytes  The number of bytes requested
2013  *	wait   Shall we wait?
2014  *
2015  * Returns:
2016  *	A pointer to the alloced memory or possibly
2017  *	NULL if M_NOWAIT is set.
2018  */
2019 static void *
2020 noobj_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *flags,
2021     int wait)
2022 {
2023 	TAILQ_HEAD(, vm_page) alloctail;
2024 	u_long npages;
2025 	vm_offset_t retkva, zkva;
2026 	vm_page_t p, p_next;
2027 	uma_keg_t keg;
2028 	int req;
2029 
2030 	TAILQ_INIT(&alloctail);
2031 	keg = zone->uz_keg;
2032 	req = VM_ALLOC_INTERRUPT | VM_ALLOC_WIRED;
2033 	if ((wait & M_WAITOK) != 0)
2034 		req |= VM_ALLOC_WAITOK;
2035 
2036 	npages = howmany(bytes, PAGE_SIZE);
2037 	while (npages > 0) {
2038 		p = vm_page_alloc_noobj_domain(domain, req);
2039 		if (p != NULL) {
2040 			/*
2041 			 * Since the page does not belong to an object, its
2042 			 * listq is unused.
2043 			 */
2044 			TAILQ_INSERT_TAIL(&alloctail, p, listq);
2045 			npages--;
2046 			continue;
2047 		}
2048 		/*
2049 		 * Page allocation failed, free intermediate pages and
2050 		 * exit.
2051 		 */
2052 		TAILQ_FOREACH_SAFE(p, &alloctail, listq, p_next) {
2053 			vm_page_unwire_noq(p);
2054 			vm_page_free(p);
2055 		}
2056 		return (NULL);
2057 	}
2058 	*flags = UMA_SLAB_PRIV;
2059 	zkva = keg->uk_kva +
2060 	    atomic_fetchadd_long(&keg->uk_offset, round_page(bytes));
2061 	retkva = zkva;
2062 	TAILQ_FOREACH(p, &alloctail, listq) {
2063 		pmap_qenter(zkva, &p, 1);
2064 		zkva += PAGE_SIZE;
2065 	}
2066 
2067 	return ((void *)retkva);
2068 }
2069 
2070 /*
2071  * Allocate physically contiguous pages.
2072  */
2073 static void *
2074 contig_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
2075     int wait)
2076 {
2077 
2078 	*pflag = UMA_SLAB_KERNEL;
2079 	return ((void *)kmem_alloc_contig_domainset(DOMAINSET_FIXED(domain),
2080 	    bytes, wait, 0, ~(vm_paddr_t)0, 1, 0, VM_MEMATTR_DEFAULT));
2081 }
2082 
2083 #if defined(UMA_USE_DMAP) && !defined(UMA_MD_SMALL_ALLOC)
2084 void *
2085 uma_small_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *flags,
2086     int wait)
2087 {
2088 	vm_page_t m;
2089 	vm_paddr_t pa;
2090 	void *va;
2091 
2092 	*flags = UMA_SLAB_PRIV;
2093 	m = vm_page_alloc_noobj_domain(domain,
2094 	    malloc2vm_flags(wait) | VM_ALLOC_WIRED);
2095 	if (m == NULL)
2096 		return (NULL);
2097 	pa = m->phys_addr;
2098 	if ((wait & M_NODUMP) == 0)
2099 		dump_add_page(pa);
2100 	va = (void *)PHYS_TO_DMAP(pa);
2101 	return (va);
2102 }
2103 #endif
2104 
2105 /*
2106  * Frees a number of pages to the system
2107  *
2108  * Arguments:
2109  *	mem   A pointer to the memory to be freed
2110  *	size  The size of the memory being freed
2111  *	flags The original p->us_flags field
2112  *
2113  * Returns:
2114  *	Nothing
2115  */
2116 static void
2117 page_free(void *mem, vm_size_t size, uint8_t flags)
2118 {
2119 
2120 	if ((flags & UMA_SLAB_BOOT) != 0) {
2121 		startup_free(mem, size);
2122 		return;
2123 	}
2124 
2125 	KASSERT((flags & UMA_SLAB_KERNEL) != 0,
2126 	    ("UMA: page_free used with invalid flags %x", flags));
2127 
2128 	kmem_free(mem, size);
2129 }
2130 
2131 /*
2132  * Frees pcpu zone allocations
2133  *
2134  * Arguments:
2135  *	mem   A pointer to the memory to be freed
2136  *	size  The size of the memory being freed
2137  *	flags The original p->us_flags field
2138  *
2139  * Returns:
2140  *	Nothing
2141  */
2142 static void
2143 pcpu_page_free(void *mem, vm_size_t size, uint8_t flags)
2144 {
2145 	vm_offset_t sva, curva;
2146 	vm_paddr_t paddr;
2147 	vm_page_t m;
2148 
2149 	MPASS(size == (mp_maxid+1)*PAGE_SIZE);
2150 
2151 	if ((flags & UMA_SLAB_BOOT) != 0) {
2152 		startup_free(mem, size);
2153 		return;
2154 	}
2155 
2156 	sva = (vm_offset_t)mem;
2157 	for (curva = sva; curva < sva + size; curva += PAGE_SIZE) {
2158 		paddr = pmap_kextract(curva);
2159 		m = PHYS_TO_VM_PAGE(paddr);
2160 		vm_page_unwire_noq(m);
2161 		vm_page_free(m);
2162 	}
2163 	pmap_qremove(sva, size >> PAGE_SHIFT);
2164 	kva_free(sva, size);
2165 }
2166 
2167 #if defined(UMA_USE_DMAP) && !defined(UMA_MD_SMALL_ALLOC)
2168 void
2169 uma_small_free(void *mem, vm_size_t size, uint8_t flags)
2170 {
2171 	vm_page_t m;
2172 	vm_paddr_t pa;
2173 
2174 	pa = DMAP_TO_PHYS((vm_offset_t)mem);
2175 	dump_drop_page(pa);
2176 	m = PHYS_TO_VM_PAGE(pa);
2177 	vm_page_unwire_noq(m);
2178 	vm_page_free(m);
2179 }
2180 #endif
2181 
2182 /*
2183  * Zero fill initializer
2184  *
2185  * Arguments/Returns follow uma_init specifications
2186  */
2187 static int
2188 zero_init(void *mem, int size, int flags)
2189 {
2190 	bzero(mem, size);
2191 	return (0);
2192 }
2193 
2194 #ifdef INVARIANTS
2195 static struct noslabbits *
2196 slab_dbg_bits(uma_slab_t slab, uma_keg_t keg)
2197 {
2198 
2199 	return ((void *)((char *)&slab->us_free + BITSET_SIZE(keg->uk_ipers)));
2200 }
2201 #endif
2202 
2203 /*
2204  * Actual size of embedded struct slab (!OFFPAGE).
2205  */
2206 static size_t
2207 slab_sizeof(int nitems)
2208 {
2209 	size_t s;
2210 
2211 	s = sizeof(struct uma_slab) + BITSET_SIZE(nitems) * SLAB_BITSETS;
2212 	return (roundup(s, UMA_ALIGN_PTR + 1));
2213 }
2214 
2215 #define	UMA_FIXPT_SHIFT	31
2216 #define	UMA_FRAC_FIXPT(n, d)						\
2217 	((uint32_t)(((uint64_t)(n) << UMA_FIXPT_SHIFT) / (d)))
2218 #define	UMA_FIXPT_PCT(f)						\
2219 	((u_int)(((uint64_t)100 * (f)) >> UMA_FIXPT_SHIFT))
2220 #define	UMA_PCT_FIXPT(pct)	UMA_FRAC_FIXPT((pct), 100)
2221 #define	UMA_MIN_EFF	UMA_PCT_FIXPT(100 - UMA_MAX_WASTE)
2222 
2223 /*
2224  * Compute the number of items that will fit in a slab.  If hdr is true, the
2225  * item count may be limited to provide space in the slab for an inline slab
2226  * header.  Otherwise, all slab space will be provided for item storage.
2227  */
2228 static u_int
2229 slab_ipers_hdr(u_int size, u_int rsize, u_int slabsize, bool hdr)
2230 {
2231 	u_int ipers;
2232 	u_int padpi;
2233 
2234 	/* The padding between items is not needed after the last item. */
2235 	padpi = rsize - size;
2236 
2237 	if (hdr) {
2238 		/*
2239 		 * Start with the maximum item count and remove items until
2240 		 * the slab header first alongside the allocatable memory.
2241 		 */
2242 		for (ipers = MIN(SLAB_MAX_SETSIZE,
2243 		    (slabsize + padpi - slab_sizeof(1)) / rsize);
2244 		    ipers > 0 &&
2245 		    ipers * rsize - padpi + slab_sizeof(ipers) > slabsize;
2246 		    ipers--)
2247 			continue;
2248 	} else {
2249 		ipers = MIN((slabsize + padpi) / rsize, SLAB_MAX_SETSIZE);
2250 	}
2251 
2252 	return (ipers);
2253 }
2254 
2255 struct keg_layout_result {
2256 	u_int format;
2257 	u_int slabsize;
2258 	u_int ipers;
2259 	u_int eff;
2260 };
2261 
2262 static void
2263 keg_layout_one(uma_keg_t keg, u_int rsize, u_int slabsize, u_int fmt,
2264     struct keg_layout_result *kl)
2265 {
2266 	u_int total;
2267 
2268 	kl->format = fmt;
2269 	kl->slabsize = slabsize;
2270 
2271 	/* Handle INTERNAL as inline with an extra page. */
2272 	if ((fmt & UMA_ZFLAG_INTERNAL) != 0) {
2273 		kl->format &= ~UMA_ZFLAG_INTERNAL;
2274 		kl->slabsize += PAGE_SIZE;
2275 	}
2276 
2277 	kl->ipers = slab_ipers_hdr(keg->uk_size, rsize, kl->slabsize,
2278 	    (fmt & UMA_ZFLAG_OFFPAGE) == 0);
2279 
2280 	/* Account for memory used by an offpage slab header. */
2281 	total = kl->slabsize;
2282 	if ((fmt & UMA_ZFLAG_OFFPAGE) != 0)
2283 		total += slabzone(kl->ipers)->uz_keg->uk_rsize;
2284 
2285 	kl->eff = UMA_FRAC_FIXPT(kl->ipers * rsize, total);
2286 }
2287 
2288 /*
2289  * Determine the format of a uma keg.  This determines where the slab header
2290  * will be placed (inline or offpage) and calculates ipers, rsize, and ppera.
2291  *
2292  * Arguments
2293  *	keg  The zone we should initialize
2294  *
2295  * Returns
2296  *	Nothing
2297  */
2298 static void
2299 keg_layout(uma_keg_t keg)
2300 {
2301 	struct keg_layout_result kl = {}, kl_tmp;
2302 	u_int fmts[2];
2303 	u_int alignsize;
2304 	u_int nfmt;
2305 	u_int pages;
2306 	u_int rsize;
2307 	u_int slabsize;
2308 	u_int i, j;
2309 
2310 	KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0 ||
2311 	    (keg->uk_size <= UMA_PCPU_ALLOC_SIZE &&
2312 	     (keg->uk_flags & UMA_ZONE_CACHESPREAD) == 0),
2313 	    ("%s: cannot configure for PCPU: keg=%s, size=%u, flags=0x%b",
2314 	     __func__, keg->uk_name, keg->uk_size, keg->uk_flags,
2315 	     PRINT_UMA_ZFLAGS));
2316 	KASSERT((keg->uk_flags & (UMA_ZFLAG_INTERNAL | UMA_ZONE_VM)) == 0 ||
2317 	    (keg->uk_flags & (UMA_ZONE_NOTOUCH | UMA_ZONE_PCPU)) == 0,
2318 	    ("%s: incompatible flags 0x%b", __func__, keg->uk_flags,
2319 	     PRINT_UMA_ZFLAGS));
2320 
2321 	alignsize = keg->uk_align + 1;
2322 #ifdef KASAN
2323 	/*
2324 	 * ASAN requires that each allocation be aligned to the shadow map
2325 	 * scale factor.
2326 	 */
2327 	if (alignsize < KASAN_SHADOW_SCALE)
2328 		alignsize = KASAN_SHADOW_SCALE;
2329 #endif
2330 
2331 	/*
2332 	 * Calculate the size of each allocation (rsize) according to
2333 	 * alignment.  If the requested size is smaller than we have
2334 	 * allocation bits for we round it up.
2335 	 */
2336 	rsize = MAX(keg->uk_size, UMA_SMALLEST_UNIT);
2337 	rsize = roundup2(rsize, alignsize);
2338 
2339 	if ((keg->uk_flags & UMA_ZONE_CACHESPREAD) != 0) {
2340 		/*
2341 		 * We want one item to start on every align boundary in a page.
2342 		 * To do this we will span pages.  We will also extend the item
2343 		 * by the size of align if it is an even multiple of align.
2344 		 * Otherwise, it would fall on the same boundary every time.
2345 		 */
2346 		if ((rsize & alignsize) == 0)
2347 			rsize += alignsize;
2348 		slabsize = rsize * (PAGE_SIZE / alignsize);
2349 		slabsize = MIN(slabsize, rsize * SLAB_MAX_SETSIZE);
2350 		slabsize = MIN(slabsize, UMA_CACHESPREAD_MAX_SIZE);
2351 		slabsize = round_page(slabsize);
2352 	} else {
2353 		/*
2354 		 * Start with a slab size of as many pages as it takes to
2355 		 * represent a single item.  We will try to fit as many
2356 		 * additional items into the slab as possible.
2357 		 */
2358 		slabsize = round_page(keg->uk_size);
2359 	}
2360 
2361 	/* Build a list of all of the available formats for this keg. */
2362 	nfmt = 0;
2363 
2364 	/* Evaluate an inline slab layout. */
2365 	if ((keg->uk_flags & (UMA_ZONE_NOTOUCH | UMA_ZONE_PCPU)) == 0)
2366 		fmts[nfmt++] = 0;
2367 
2368 	/* TODO: vm_page-embedded slab. */
2369 
2370 	/*
2371 	 * We can't do OFFPAGE if we're internal or if we've been
2372 	 * asked to not go to the VM for buckets.  If we do this we
2373 	 * may end up going to the VM for slabs which we do not want
2374 	 * to do if we're UMA_ZONE_VM, which clearly forbids it.
2375 	 * In those cases, evaluate a pseudo-format called INTERNAL
2376 	 * which has an inline slab header and one extra page to
2377 	 * guarantee that it fits.
2378 	 *
2379 	 * Otherwise, see if using an OFFPAGE slab will improve our
2380 	 * efficiency.
2381 	 */
2382 	if ((keg->uk_flags & (UMA_ZFLAG_INTERNAL | UMA_ZONE_VM)) != 0)
2383 		fmts[nfmt++] = UMA_ZFLAG_INTERNAL;
2384 	else
2385 		fmts[nfmt++] = UMA_ZFLAG_OFFPAGE;
2386 
2387 	/*
2388 	 * Choose a slab size and format which satisfy the minimum efficiency.
2389 	 * Prefer the smallest slab size that meets the constraints.
2390 	 *
2391 	 * Start with a minimum slab size, to accommodate CACHESPREAD.  Then,
2392 	 * for small items (up to PAGE_SIZE), the iteration increment is one
2393 	 * page; and for large items, the increment is one item.
2394 	 */
2395 	i = (slabsize + rsize - keg->uk_size) / MAX(PAGE_SIZE, rsize);
2396 	KASSERT(i >= 1, ("keg %s(%p) flags=0x%b slabsize=%u, rsize=%u, i=%u",
2397 	    keg->uk_name, keg, keg->uk_flags, PRINT_UMA_ZFLAGS, slabsize,
2398 	    rsize, i));
2399 	for ( ; ; i++) {
2400 		slabsize = (rsize <= PAGE_SIZE) ? ptoa(i) :
2401 		    round_page(rsize * (i - 1) + keg->uk_size);
2402 
2403 		for (j = 0; j < nfmt; j++) {
2404 			/* Only if we have no viable format yet. */
2405 			if ((fmts[j] & UMA_ZFLAG_INTERNAL) != 0 &&
2406 			    kl.ipers > 0)
2407 				continue;
2408 
2409 			keg_layout_one(keg, rsize, slabsize, fmts[j], &kl_tmp);
2410 			if (kl_tmp.eff <= kl.eff)
2411 				continue;
2412 
2413 			kl = kl_tmp;
2414 
2415 			CTR6(KTR_UMA, "keg %s layout: format %#x "
2416 			    "(ipers %u * rsize %u) / slabsize %#x = %u%% eff",
2417 			    keg->uk_name, kl.format, kl.ipers, rsize,
2418 			    kl.slabsize, UMA_FIXPT_PCT(kl.eff));
2419 
2420 			/* Stop when we reach the minimum efficiency. */
2421 			if (kl.eff >= UMA_MIN_EFF)
2422 				break;
2423 		}
2424 
2425 		if (kl.eff >= UMA_MIN_EFF || !multipage_slabs ||
2426 		    slabsize >= SLAB_MAX_SETSIZE * rsize ||
2427 		    (keg->uk_flags & (UMA_ZONE_PCPU | UMA_ZONE_CONTIG)) != 0)
2428 			break;
2429 	}
2430 
2431 	pages = atop(kl.slabsize);
2432 	if ((keg->uk_flags & UMA_ZONE_PCPU) != 0)
2433 		pages *= mp_maxid + 1;
2434 
2435 	keg->uk_rsize = rsize;
2436 	keg->uk_ipers = kl.ipers;
2437 	keg->uk_ppera = pages;
2438 	keg->uk_flags |= kl.format;
2439 
2440 	/*
2441 	 * How do we find the slab header if it is offpage or if not all item
2442 	 * start addresses are in the same page?  We could solve the latter
2443 	 * case with vaddr alignment, but we don't.
2444 	 */
2445 	if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0 ||
2446 	    (keg->uk_ipers - 1) * rsize >= PAGE_SIZE) {
2447 		if ((keg->uk_flags & UMA_ZONE_NOTPAGE) != 0)
2448 			keg->uk_flags |= UMA_ZFLAG_HASH;
2449 		else
2450 			keg->uk_flags |= UMA_ZFLAG_VTOSLAB;
2451 	}
2452 
2453 	CTR6(KTR_UMA, "%s: keg=%s, flags=%#x, rsize=%u, ipers=%u, ppera=%u",
2454 	    __func__, keg->uk_name, keg->uk_flags, rsize, keg->uk_ipers,
2455 	    pages);
2456 	KASSERT(keg->uk_ipers > 0 && keg->uk_ipers <= SLAB_MAX_SETSIZE,
2457 	    ("%s: keg=%s, flags=0x%b, rsize=%u, ipers=%u, ppera=%u", __func__,
2458 	     keg->uk_name, keg->uk_flags, PRINT_UMA_ZFLAGS, rsize,
2459 	     keg->uk_ipers, pages));
2460 }
2461 
2462 /*
2463  * Keg header ctor.  This initializes all fields, locks, etc.  And inserts
2464  * the keg onto the global keg list.
2465  *
2466  * Arguments/Returns follow uma_ctor specifications
2467  *	udata  Actually uma_kctor_args
2468  */
2469 static int
2470 keg_ctor(void *mem, int size, void *udata, int flags)
2471 {
2472 	struct uma_kctor_args *arg = udata;
2473 	uma_keg_t keg = mem;
2474 	uma_zone_t zone;
2475 	int i;
2476 
2477 	bzero(keg, size);
2478 	keg->uk_size = arg->size;
2479 	keg->uk_init = arg->uminit;
2480 	keg->uk_fini = arg->fini;
2481 	keg->uk_align = arg->align;
2482 	keg->uk_reserve = 0;
2483 	keg->uk_flags = arg->flags;
2484 
2485 	/*
2486 	 * We use a global round-robin policy by default.  Zones with
2487 	 * UMA_ZONE_FIRSTTOUCH set will use first-touch instead, in which
2488 	 * case the iterator is never run.
2489 	 */
2490 	keg->uk_dr.dr_policy = DOMAINSET_RR();
2491 	keg->uk_dr.dr_iter = 0;
2492 
2493 	/*
2494 	 * The primary zone is passed to us at keg-creation time.
2495 	 */
2496 	zone = arg->zone;
2497 	keg->uk_name = zone->uz_name;
2498 
2499 	if (arg->flags & UMA_ZONE_ZINIT)
2500 		keg->uk_init = zero_init;
2501 
2502 	if (arg->flags & UMA_ZONE_MALLOC)
2503 		keg->uk_flags |= UMA_ZFLAG_VTOSLAB;
2504 
2505 #ifndef SMP
2506 	keg->uk_flags &= ~UMA_ZONE_PCPU;
2507 #endif
2508 
2509 	keg_layout(keg);
2510 
2511 	/*
2512 	 * Use a first-touch NUMA policy for kegs that pmap_extract() will
2513 	 * work on.  Use round-robin for everything else.
2514 	 *
2515 	 * Zones may override the default by specifying either.
2516 	 */
2517 #ifdef NUMA
2518 	if ((keg->uk_flags &
2519 	    (UMA_ZONE_ROUNDROBIN | UMA_ZFLAG_CACHE | UMA_ZONE_NOTPAGE)) == 0)
2520 		keg->uk_flags |= UMA_ZONE_FIRSTTOUCH;
2521 	else if ((keg->uk_flags & UMA_ZONE_FIRSTTOUCH) == 0)
2522 		keg->uk_flags |= UMA_ZONE_ROUNDROBIN;
2523 #endif
2524 
2525 	/*
2526 	 * If we haven't booted yet we need allocations to go through the
2527 	 * startup cache until the vm is ready.
2528 	 */
2529 #ifdef UMA_USE_DMAP
2530 	if (keg->uk_ppera == 1)
2531 		keg->uk_allocf = uma_small_alloc;
2532 	else
2533 #endif
2534 	if (booted < BOOT_KVA)
2535 		keg->uk_allocf = startup_alloc;
2536 	else if (keg->uk_flags & UMA_ZONE_PCPU)
2537 		keg->uk_allocf = pcpu_page_alloc;
2538 	else if ((keg->uk_flags & UMA_ZONE_CONTIG) != 0 && keg->uk_ppera > 1)
2539 		keg->uk_allocf = contig_alloc;
2540 	else
2541 		keg->uk_allocf = page_alloc;
2542 #ifdef UMA_USE_DMAP
2543 	if (keg->uk_ppera == 1)
2544 		keg->uk_freef = uma_small_free;
2545 	else
2546 #endif
2547 	if (keg->uk_flags & UMA_ZONE_PCPU)
2548 		keg->uk_freef = pcpu_page_free;
2549 	else
2550 		keg->uk_freef = page_free;
2551 
2552 	/*
2553 	 * Initialize keg's locks.
2554 	 */
2555 	for (i = 0; i < vm_ndomains; i++)
2556 		KEG_LOCK_INIT(keg, i, (arg->flags & UMA_ZONE_MTXCLASS));
2557 
2558 	/*
2559 	 * If we're putting the slab header in the actual page we need to
2560 	 * figure out where in each page it goes.  See slab_sizeof
2561 	 * definition.
2562 	 */
2563 	if (!(keg->uk_flags & UMA_ZFLAG_OFFPAGE)) {
2564 		size_t shsize;
2565 
2566 		shsize = slab_sizeof(keg->uk_ipers);
2567 		keg->uk_pgoff = (PAGE_SIZE * keg->uk_ppera) - shsize;
2568 		/*
2569 		 * The only way the following is possible is if with our
2570 		 * UMA_ALIGN_PTR adjustments we are now bigger than
2571 		 * UMA_SLAB_SIZE.  I haven't checked whether this is
2572 		 * mathematically possible for all cases, so we make
2573 		 * sure here anyway.
2574 		 */
2575 		KASSERT(keg->uk_pgoff + shsize <= PAGE_SIZE * keg->uk_ppera,
2576 		    ("zone %s ipers %d rsize %d size %d slab won't fit",
2577 		    zone->uz_name, keg->uk_ipers, keg->uk_rsize, keg->uk_size));
2578 	}
2579 
2580 	if (keg->uk_flags & UMA_ZFLAG_HASH)
2581 		hash_alloc(&keg->uk_hash, 0);
2582 
2583 	CTR3(KTR_UMA, "keg_ctor %p zone %s(%p)", keg, zone->uz_name, zone);
2584 
2585 	LIST_INSERT_HEAD(&keg->uk_zones, zone, uz_link);
2586 
2587 	rw_wlock(&uma_rwlock);
2588 	LIST_INSERT_HEAD(&uma_kegs, keg, uk_link);
2589 	rw_wunlock(&uma_rwlock);
2590 	return (0);
2591 }
2592 
2593 static void
2594 zone_kva_available(uma_zone_t zone, void *unused)
2595 {
2596 	uma_keg_t keg;
2597 
2598 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
2599 		return;
2600 	KEG_GET(zone, keg);
2601 
2602 	if (keg->uk_allocf == startup_alloc) {
2603 		/* Switch to the real allocator. */
2604 		if (keg->uk_flags & UMA_ZONE_PCPU)
2605 			keg->uk_allocf = pcpu_page_alloc;
2606 		else if ((keg->uk_flags & UMA_ZONE_CONTIG) != 0 &&
2607 		    keg->uk_ppera > 1)
2608 			keg->uk_allocf = contig_alloc;
2609 		else
2610 			keg->uk_allocf = page_alloc;
2611 	}
2612 }
2613 
2614 static void
2615 zone_alloc_counters(uma_zone_t zone, void *unused)
2616 {
2617 
2618 	zone->uz_allocs = counter_u64_alloc(M_WAITOK);
2619 	zone->uz_frees = counter_u64_alloc(M_WAITOK);
2620 	zone->uz_fails = counter_u64_alloc(M_WAITOK);
2621 	zone->uz_xdomain = counter_u64_alloc(M_WAITOK);
2622 }
2623 
2624 static void
2625 zone_alloc_sysctl(uma_zone_t zone, void *unused)
2626 {
2627 	uma_zone_domain_t zdom;
2628 	uma_domain_t dom;
2629 	uma_keg_t keg;
2630 	struct sysctl_oid *oid, *domainoid;
2631 	int domains, i, cnt;
2632 	static const char *nokeg = "cache zone";
2633 	char *c;
2634 
2635 	/*
2636 	 * Make a sysctl safe copy of the zone name by removing
2637 	 * any special characters and handling dups by appending
2638 	 * an index.
2639 	 */
2640 	if (zone->uz_namecnt != 0) {
2641 		/* Count the number of decimal digits and '_' separator. */
2642 		for (i = 1, cnt = zone->uz_namecnt; cnt != 0; i++)
2643 			cnt /= 10;
2644 		zone->uz_ctlname = malloc(strlen(zone->uz_name) + i + 1,
2645 		    M_UMA, M_WAITOK);
2646 		sprintf(zone->uz_ctlname, "%s_%d", zone->uz_name,
2647 		    zone->uz_namecnt);
2648 	} else
2649 		zone->uz_ctlname = strdup(zone->uz_name, M_UMA);
2650 	for (c = zone->uz_ctlname; *c != '\0'; c++)
2651 		if (strchr("./\\ -", *c) != NULL)
2652 			*c = '_';
2653 
2654 	/*
2655 	 * Basic parameters at the root.
2656 	 */
2657 	zone->uz_oid = SYSCTL_ADD_NODE(NULL, SYSCTL_STATIC_CHILDREN(_vm_uma),
2658 	    OID_AUTO, zone->uz_ctlname, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2659 	oid = zone->uz_oid;
2660 	SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2661 	    "size", CTLFLAG_RD, &zone->uz_size, 0, "Allocation size");
2662 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2663 	    "flags", CTLFLAG_RD | CTLTYPE_STRING | CTLFLAG_MPSAFE,
2664 	    zone, 0, sysctl_handle_uma_zone_flags, "A",
2665 	    "Allocator configuration flags");
2666 	SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2667 	    "bucket_size", CTLFLAG_RD, &zone->uz_bucket_size, 0,
2668 	    "Desired per-cpu cache size");
2669 	SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2670 	    "bucket_size_max", CTLFLAG_RD, &zone->uz_bucket_size_max, 0,
2671 	    "Maximum allowed per-cpu cache size");
2672 
2673 	/*
2674 	 * keg if present.
2675 	 */
2676 	if ((zone->uz_flags & UMA_ZFLAG_HASH) == 0)
2677 		domains = vm_ndomains;
2678 	else
2679 		domains = 1;
2680 	oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2681 	    "keg", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2682 	keg = zone->uz_keg;
2683 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) == 0) {
2684 		SYSCTL_ADD_CONST_STRING(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2685 		    "name", CTLFLAG_RD, keg->uk_name, "Keg name");
2686 		SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2687 		    "rsize", CTLFLAG_RD, &keg->uk_rsize, 0,
2688 		    "Real object size with alignment");
2689 		SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2690 		    "ppera", CTLFLAG_RD, &keg->uk_ppera, 0,
2691 		    "pages per-slab allocation");
2692 		SYSCTL_ADD_U16(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2693 		    "ipers", CTLFLAG_RD, &keg->uk_ipers, 0,
2694 		    "items available per-slab");
2695 		SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2696 		    "align", CTLFLAG_RD, &keg->uk_align, 0,
2697 		    "item alignment mask");
2698 		SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2699 		    "reserve", CTLFLAG_RD, &keg->uk_reserve, 0,
2700 		    "number of reserved items");
2701 		SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2702 		    "efficiency", CTLFLAG_RD | CTLTYPE_INT | CTLFLAG_MPSAFE,
2703 		    keg, 0, sysctl_handle_uma_slab_efficiency, "I",
2704 		    "Slab utilization (100 - internal fragmentation %)");
2705 		domainoid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(oid),
2706 		    OID_AUTO, "domain", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2707 		for (i = 0; i < domains; i++) {
2708 			dom = &keg->uk_domain[i];
2709 			oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(domainoid),
2710 			    OID_AUTO, VM_DOMAIN(i)->vmd_name,
2711 			    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2712 			SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2713 			    "pages", CTLFLAG_RD, &dom->ud_pages, 0,
2714 			    "Total pages currently allocated from VM");
2715 			SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2716 			    "free_items", CTLFLAG_RD, &dom->ud_free_items, 0,
2717 			    "Items free in the slab layer");
2718 			SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2719 			    "free_slabs", CTLFLAG_RD, &dom->ud_free_slabs, 0,
2720 			    "Unused slabs");
2721 		}
2722 	} else
2723 		SYSCTL_ADD_CONST_STRING(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2724 		    "name", CTLFLAG_RD, nokeg, "Keg name");
2725 
2726 	/*
2727 	 * Information about zone limits.
2728 	 */
2729 	oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2730 	    "limit", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2731 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2732 	    "items", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2733 	    zone, 0, sysctl_handle_uma_zone_items, "QU",
2734 	    "Current number of allocated items if limit is set");
2735 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2736 	    "max_items", CTLFLAG_RD, &zone->uz_max_items, 0,
2737 	    "Maximum number of allocated and cached items");
2738 	SYSCTL_ADD_U32(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2739 	    "sleepers", CTLFLAG_RD, &zone->uz_sleepers, 0,
2740 	    "Number of threads sleeping at limit");
2741 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2742 	    "sleeps", CTLFLAG_RD, &zone->uz_sleeps, 0,
2743 	    "Total zone limit sleeps");
2744 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2745 	    "bucket_max", CTLFLAG_RD, &zone->uz_bucket_max, 0,
2746 	    "Maximum number of items in each domain's bucket cache");
2747 
2748 	/*
2749 	 * Per-domain zone information.
2750 	 */
2751 	domainoid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid),
2752 	    OID_AUTO, "domain", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2753 	for (i = 0; i < domains; i++) {
2754 		zdom = ZDOM_GET(zone, i);
2755 		oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(domainoid),
2756 		    OID_AUTO, VM_DOMAIN(i)->vmd_name,
2757 		    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2758 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2759 		    "nitems", CTLFLAG_RD, &zdom->uzd_nitems,
2760 		    "number of items in this domain");
2761 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2762 		    "imax", CTLFLAG_RD, &zdom->uzd_imax,
2763 		    "maximum item count in this period");
2764 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2765 		    "imin", CTLFLAG_RD, &zdom->uzd_imin,
2766 		    "minimum item count in this period");
2767 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2768 		    "bimin", CTLFLAG_RD, &zdom->uzd_bimin,
2769 		    "Minimum item count in this batch");
2770 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2771 		    "wss", CTLFLAG_RD, &zdom->uzd_wss,
2772 		    "Working set size");
2773 		SYSCTL_ADD_LONG(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2774 		    "limin", CTLFLAG_RD, &zdom->uzd_limin,
2775 		    "Long time minimum item count");
2776 		SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2777 		    "timin", CTLFLAG_RD, &zdom->uzd_timin, 0,
2778 		    "Time since zero long time minimum item count");
2779 	}
2780 
2781 	/*
2782 	 * General statistics.
2783 	 */
2784 	oid = SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(zone->uz_oid), OID_AUTO,
2785 	    "stats", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
2786 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2787 	    "current", CTLFLAG_RD | CTLTYPE_INT | CTLFLAG_MPSAFE,
2788 	    zone, 1, sysctl_handle_uma_zone_cur, "I",
2789 	    "Current number of allocated items");
2790 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2791 	    "allocs", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2792 	    zone, 0, sysctl_handle_uma_zone_allocs, "QU",
2793 	    "Total allocation calls");
2794 	SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2795 	    "frees", CTLFLAG_RD | CTLTYPE_U64 | CTLFLAG_MPSAFE,
2796 	    zone, 0, sysctl_handle_uma_zone_frees, "QU",
2797 	    "Total free calls");
2798 	SYSCTL_ADD_COUNTER_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2799 	    "fails", CTLFLAG_RD, &zone->uz_fails,
2800 	    "Number of allocation failures");
2801 	SYSCTL_ADD_COUNTER_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO,
2802 	    "xdomain", CTLFLAG_RD, &zone->uz_xdomain,
2803 	    "Free calls from the wrong domain");
2804 }
2805 
2806 struct uma_zone_count {
2807 	const char	*name;
2808 	int		count;
2809 };
2810 
2811 static void
2812 zone_count(uma_zone_t zone, void *arg)
2813 {
2814 	struct uma_zone_count *cnt;
2815 
2816 	cnt = arg;
2817 	/*
2818 	 * Some zones are rapidly created with identical names and
2819 	 * destroyed out of order.  This can lead to gaps in the count.
2820 	 * Use one greater than the maximum observed for this name.
2821 	 */
2822 	if (strcmp(zone->uz_name, cnt->name) == 0)
2823 		cnt->count = MAX(cnt->count,
2824 		    zone->uz_namecnt + 1);
2825 }
2826 
2827 static void
2828 zone_update_caches(uma_zone_t zone)
2829 {
2830 	int i;
2831 
2832 	for (i = 0; i <= mp_maxid; i++) {
2833 		cache_set_uz_size(&zone->uz_cpu[i], zone->uz_size);
2834 		cache_set_uz_flags(&zone->uz_cpu[i], zone->uz_flags);
2835 	}
2836 }
2837 
2838 /*
2839  * Zone header ctor.  This initializes all fields, locks, etc.
2840  *
2841  * Arguments/Returns follow uma_ctor specifications
2842  *	udata  Actually uma_zctor_args
2843  */
2844 static int
2845 zone_ctor(void *mem, int size, void *udata, int flags)
2846 {
2847 	struct uma_zone_count cnt;
2848 	struct uma_zctor_args *arg = udata;
2849 	uma_zone_domain_t zdom;
2850 	uma_zone_t zone = mem;
2851 	uma_zone_t z;
2852 	uma_keg_t keg;
2853 	int i;
2854 
2855 	bzero(zone, size);
2856 	zone->uz_name = arg->name;
2857 	zone->uz_ctor = arg->ctor;
2858 	zone->uz_dtor = arg->dtor;
2859 	zone->uz_init = NULL;
2860 	zone->uz_fini = NULL;
2861 	zone->uz_sleeps = 0;
2862 	zone->uz_bucket_size = 0;
2863 	zone->uz_bucket_size_min = 0;
2864 	zone->uz_bucket_size_max = BUCKET_MAX;
2865 	zone->uz_flags = (arg->flags & UMA_ZONE_SMR);
2866 	zone->uz_warning = NULL;
2867 	/* The domain structures follow the cpu structures. */
2868 	zone->uz_bucket_max = ULONG_MAX;
2869 	timevalclear(&zone->uz_ratecheck);
2870 
2871 	/* Count the number of duplicate names. */
2872 	cnt.name = arg->name;
2873 	cnt.count = 0;
2874 	zone_foreach(zone_count, &cnt);
2875 	zone->uz_namecnt = cnt.count;
2876 	ZONE_CROSS_LOCK_INIT(zone);
2877 
2878 	for (i = 0; i < vm_ndomains; i++) {
2879 		zdom = ZDOM_GET(zone, i);
2880 		ZDOM_LOCK_INIT(zone, zdom, (arg->flags & UMA_ZONE_MTXCLASS));
2881 		STAILQ_INIT(&zdom->uzd_buckets);
2882 	}
2883 
2884 #if defined(INVARIANTS) && !defined(KASAN) && !defined(KMSAN)
2885 	if (arg->uminit == trash_init && arg->fini == trash_fini)
2886 		zone->uz_flags |= UMA_ZFLAG_TRASH | UMA_ZFLAG_CTORDTOR;
2887 #elif defined(KASAN)
2888 	if ((arg->flags & (UMA_ZONE_NOFREE | UMA_ZFLAG_CACHE)) != 0)
2889 		arg->flags |= UMA_ZONE_NOKASAN;
2890 #endif
2891 
2892 	/*
2893 	 * This is a pure cache zone, no kegs.
2894 	 */
2895 	if (arg->import) {
2896 		KASSERT((arg->flags & UMA_ZFLAG_CACHE) != 0,
2897 		    ("zone_ctor: Import specified for non-cache zone."));
2898 		zone->uz_flags = arg->flags;
2899 		zone->uz_size = arg->size;
2900 		zone->uz_import = arg->import;
2901 		zone->uz_release = arg->release;
2902 		zone->uz_arg = arg->arg;
2903 #ifdef NUMA
2904 		/*
2905 		 * Cache zones are round-robin unless a policy is
2906 		 * specified because they may have incompatible
2907 		 * constraints.
2908 		 */
2909 		if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) == 0)
2910 			zone->uz_flags |= UMA_ZONE_ROUNDROBIN;
2911 #endif
2912 		rw_wlock(&uma_rwlock);
2913 		LIST_INSERT_HEAD(&uma_cachezones, zone, uz_link);
2914 		rw_wunlock(&uma_rwlock);
2915 		goto out;
2916 	}
2917 
2918 	/*
2919 	 * Use the regular zone/keg/slab allocator.
2920 	 */
2921 	zone->uz_import = zone_import;
2922 	zone->uz_release = zone_release;
2923 	zone->uz_arg = zone;
2924 	keg = arg->keg;
2925 
2926 	if (arg->flags & UMA_ZONE_SECONDARY) {
2927 		KASSERT((zone->uz_flags & UMA_ZONE_SECONDARY) == 0,
2928 		    ("Secondary zone requested UMA_ZFLAG_INTERNAL"));
2929 		KASSERT(arg->keg != NULL, ("Secondary zone on zero'd keg"));
2930 		zone->uz_init = arg->uminit;
2931 		zone->uz_fini = arg->fini;
2932 		zone->uz_flags |= UMA_ZONE_SECONDARY;
2933 		rw_wlock(&uma_rwlock);
2934 		ZONE_LOCK(zone);
2935 		LIST_FOREACH(z, &keg->uk_zones, uz_link) {
2936 			if (LIST_NEXT(z, uz_link) == NULL) {
2937 				LIST_INSERT_AFTER(z, zone, uz_link);
2938 				break;
2939 			}
2940 		}
2941 		ZONE_UNLOCK(zone);
2942 		rw_wunlock(&uma_rwlock);
2943 	} else if (keg == NULL) {
2944 		if ((keg = uma_kcreate(zone, arg->size, arg->uminit, arg->fini,
2945 		    arg->align, arg->flags)) == NULL)
2946 			return (ENOMEM);
2947 	} else {
2948 		struct uma_kctor_args karg;
2949 		int error;
2950 
2951 		/* We should only be here from uma_startup() */
2952 		karg.size = arg->size;
2953 		karg.uminit = arg->uminit;
2954 		karg.fini = arg->fini;
2955 		karg.align = arg->align;
2956 		karg.flags = (arg->flags & ~UMA_ZONE_SMR);
2957 		karg.zone = zone;
2958 		error = keg_ctor(arg->keg, sizeof(struct uma_keg), &karg,
2959 		    flags);
2960 		if (error)
2961 			return (error);
2962 	}
2963 
2964 	/* Inherit properties from the keg. */
2965 	zone->uz_keg = keg;
2966 	zone->uz_size = keg->uk_size;
2967 	zone->uz_flags |= (keg->uk_flags &
2968 	    (UMA_ZONE_INHERIT | UMA_ZFLAG_INHERIT));
2969 
2970 out:
2971 	if (booted >= BOOT_PCPU) {
2972 		zone_alloc_counters(zone, NULL);
2973 		if (booted >= BOOT_RUNNING)
2974 			zone_alloc_sysctl(zone, NULL);
2975 	} else {
2976 		zone->uz_allocs = EARLY_COUNTER;
2977 		zone->uz_frees = EARLY_COUNTER;
2978 		zone->uz_fails = EARLY_COUNTER;
2979 	}
2980 
2981 	/* Caller requests a private SMR context. */
2982 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
2983 		zone->uz_smr = smr_create(zone->uz_name, 0, 0);
2984 
2985 	KASSERT((arg->flags & (UMA_ZONE_MAXBUCKET | UMA_ZONE_NOBUCKET)) !=
2986 	    (UMA_ZONE_MAXBUCKET | UMA_ZONE_NOBUCKET),
2987 	    ("Invalid zone flag combination"));
2988 	if (arg->flags & UMA_ZFLAG_INTERNAL)
2989 		zone->uz_bucket_size_max = zone->uz_bucket_size = 0;
2990 	if ((arg->flags & UMA_ZONE_MAXBUCKET) != 0)
2991 		zone->uz_bucket_size = BUCKET_MAX;
2992 	else if ((arg->flags & UMA_ZONE_NOBUCKET) != 0)
2993 		zone->uz_bucket_size = 0;
2994 	else
2995 		zone->uz_bucket_size = bucket_select(zone->uz_size);
2996 	zone->uz_bucket_size_min = zone->uz_bucket_size;
2997 	if (zone->uz_dtor != NULL || zone->uz_ctor != NULL)
2998 		zone->uz_flags |= UMA_ZFLAG_CTORDTOR;
2999 	zone_update_caches(zone);
3000 
3001 	return (0);
3002 }
3003 
3004 /*
3005  * Keg header dtor.  This frees all data, destroys locks, frees the hash
3006  * table and removes the keg from the global list.
3007  *
3008  * Arguments/Returns follow uma_dtor specifications
3009  *	udata  unused
3010  */
3011 static void
3012 keg_dtor(void *arg, int size, void *udata)
3013 {
3014 	uma_keg_t keg;
3015 	uint32_t free, pages;
3016 	int i;
3017 
3018 	keg = (uma_keg_t)arg;
3019 	free = pages = 0;
3020 	for (i = 0; i < vm_ndomains; i++) {
3021 		free += keg->uk_domain[i].ud_free_items;
3022 		pages += keg->uk_domain[i].ud_pages;
3023 		KEG_LOCK_FINI(keg, i);
3024 	}
3025 	if (pages != 0)
3026 		printf("Freed UMA keg (%s) was not empty (%u items). "
3027 		    " Lost %u pages of memory.\n",
3028 		    keg->uk_name ? keg->uk_name : "",
3029 		    pages / keg->uk_ppera * keg->uk_ipers - free, pages);
3030 
3031 	hash_free(&keg->uk_hash);
3032 }
3033 
3034 /*
3035  * Zone header dtor.
3036  *
3037  * Arguments/Returns follow uma_dtor specifications
3038  *	udata  unused
3039  */
3040 static void
3041 zone_dtor(void *arg, int size, void *udata)
3042 {
3043 	uma_zone_t zone;
3044 	uma_keg_t keg;
3045 	int i;
3046 
3047 	zone = (uma_zone_t)arg;
3048 
3049 	sysctl_remove_oid(zone->uz_oid, 1, 1);
3050 
3051 	if (!(zone->uz_flags & UMA_ZFLAG_INTERNAL))
3052 		cache_drain(zone);
3053 
3054 	rw_wlock(&uma_rwlock);
3055 	LIST_REMOVE(zone, uz_link);
3056 	rw_wunlock(&uma_rwlock);
3057 	if ((zone->uz_flags & (UMA_ZONE_SECONDARY | UMA_ZFLAG_CACHE)) == 0) {
3058 		keg = zone->uz_keg;
3059 		keg->uk_reserve = 0;
3060 	}
3061 	zone_reclaim(zone, UMA_ANYDOMAIN, M_WAITOK, true);
3062 
3063 	/*
3064 	 * We only destroy kegs from non secondary/non cache zones.
3065 	 */
3066 	if ((zone->uz_flags & (UMA_ZONE_SECONDARY | UMA_ZFLAG_CACHE)) == 0) {
3067 		keg = zone->uz_keg;
3068 		rw_wlock(&uma_rwlock);
3069 		LIST_REMOVE(keg, uk_link);
3070 		rw_wunlock(&uma_rwlock);
3071 		zone_free_item(kegs, keg, NULL, SKIP_NONE);
3072 	}
3073 	counter_u64_free(zone->uz_allocs);
3074 	counter_u64_free(zone->uz_frees);
3075 	counter_u64_free(zone->uz_fails);
3076 	counter_u64_free(zone->uz_xdomain);
3077 	free(zone->uz_ctlname, M_UMA);
3078 	for (i = 0; i < vm_ndomains; i++)
3079 		ZDOM_LOCK_FINI(ZDOM_GET(zone, i));
3080 	ZONE_CROSS_LOCK_FINI(zone);
3081 }
3082 
3083 static void
3084 zone_foreach_unlocked(void (*zfunc)(uma_zone_t, void *arg), void *arg)
3085 {
3086 	uma_keg_t keg;
3087 	uma_zone_t zone;
3088 
3089 	LIST_FOREACH(keg, &uma_kegs, uk_link) {
3090 		LIST_FOREACH(zone, &keg->uk_zones, uz_link)
3091 			zfunc(zone, arg);
3092 	}
3093 	LIST_FOREACH(zone, &uma_cachezones, uz_link)
3094 		zfunc(zone, arg);
3095 }
3096 
3097 /*
3098  * Traverses every zone in the system and calls a callback
3099  *
3100  * Arguments:
3101  *	zfunc  A pointer to a function which accepts a zone
3102  *		as an argument.
3103  *
3104  * Returns:
3105  *	Nothing
3106  */
3107 static void
3108 zone_foreach(void (*zfunc)(uma_zone_t, void *arg), void *arg)
3109 {
3110 
3111 	rw_rlock(&uma_rwlock);
3112 	zone_foreach_unlocked(zfunc, arg);
3113 	rw_runlock(&uma_rwlock);
3114 }
3115 
3116 /*
3117  * Initialize the kernel memory allocator.  This is done after pages can be
3118  * allocated but before general KVA is available.
3119  */
3120 void
3121 uma_startup1(vm_offset_t virtual_avail)
3122 {
3123 	struct uma_zctor_args args;
3124 	size_t ksize, zsize, size;
3125 	uma_keg_t primarykeg;
3126 	uintptr_t m;
3127 	int domain;
3128 	uint8_t pflag;
3129 
3130 	bootstart = bootmem = virtual_avail;
3131 
3132 	rw_init(&uma_rwlock, "UMA lock");
3133 	sx_init(&uma_reclaim_lock, "umareclaim");
3134 
3135 	ksize = sizeof(struct uma_keg) +
3136 	    (sizeof(struct uma_domain) * vm_ndomains);
3137 	ksize = roundup(ksize, UMA_SUPER_ALIGN);
3138 	zsize = sizeof(struct uma_zone) +
3139 	    (sizeof(struct uma_cache) * (mp_maxid + 1)) +
3140 	    (sizeof(struct uma_zone_domain) * vm_ndomains);
3141 	zsize = roundup(zsize, UMA_SUPER_ALIGN);
3142 
3143 	/* Allocate the zone of zones, zone of kegs, and zone of zones keg. */
3144 	size = (zsize * 2) + ksize;
3145 	for (domain = 0; domain < vm_ndomains; domain++) {
3146 		m = (uintptr_t)startup_alloc(NULL, size, domain, &pflag,
3147 		    M_NOWAIT | M_ZERO);
3148 		if (m != 0)
3149 			break;
3150 	}
3151 	zones = (uma_zone_t)m;
3152 	m += zsize;
3153 	kegs = (uma_zone_t)m;
3154 	m += zsize;
3155 	primarykeg = (uma_keg_t)m;
3156 
3157 	/* "manually" create the initial zone */
3158 	memset(&args, 0, sizeof(args));
3159 	args.name = "UMA Kegs";
3160 	args.size = ksize;
3161 	args.ctor = keg_ctor;
3162 	args.dtor = keg_dtor;
3163 	args.uminit = zero_init;
3164 	args.fini = NULL;
3165 	args.keg = primarykeg;
3166 	args.align = UMA_SUPER_ALIGN - 1;
3167 	args.flags = UMA_ZFLAG_INTERNAL;
3168 	zone_ctor(kegs, zsize, &args, M_WAITOK);
3169 
3170 	args.name = "UMA Zones";
3171 	args.size = zsize;
3172 	args.ctor = zone_ctor;
3173 	args.dtor = zone_dtor;
3174 	args.uminit = zero_init;
3175 	args.fini = NULL;
3176 	args.keg = NULL;
3177 	args.align = UMA_SUPER_ALIGN - 1;
3178 	args.flags = UMA_ZFLAG_INTERNAL;
3179 	zone_ctor(zones, zsize, &args, M_WAITOK);
3180 
3181 	/* Now make zones for slab headers */
3182 	slabzones[0] = uma_zcreate("UMA Slabs 0", SLABZONE0_SIZE,
3183 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
3184 	slabzones[1] = uma_zcreate("UMA Slabs 1", SLABZONE1_SIZE,
3185 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
3186 
3187 	hashzone = uma_zcreate("UMA Hash",
3188 	    sizeof(struct slabhead *) * UMA_HASH_SIZE_INIT,
3189 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZFLAG_INTERNAL);
3190 
3191 	bucket_init();
3192 	smr_init();
3193 }
3194 
3195 #ifndef UMA_USE_DMAP
3196 extern void vm_radix_reserve_kva(void);
3197 #endif
3198 
3199 /*
3200  * Advertise the availability of normal kva allocations and switch to
3201  * the default back-end allocator.  Marks the KVA we consumed on startup
3202  * as used in the map.
3203  */
3204 void
3205 uma_startup2(void)
3206 {
3207 
3208 	if (bootstart != bootmem) {
3209 		vm_map_lock(kernel_map);
3210 		(void)vm_map_insert(kernel_map, NULL, 0, bootstart, bootmem,
3211 		    VM_PROT_RW, VM_PROT_RW, MAP_NOFAULT);
3212 		vm_map_unlock(kernel_map);
3213 	}
3214 
3215 #ifndef UMA_USE_DMAP
3216 	/* Set up radix zone to use noobj_alloc. */
3217 	vm_radix_reserve_kva();
3218 #endif
3219 
3220 	booted = BOOT_KVA;
3221 	zone_foreach_unlocked(zone_kva_available, NULL);
3222 	bucket_enable();
3223 }
3224 
3225 /*
3226  * Allocate counters as early as possible so that boot-time allocations are
3227  * accounted more precisely.
3228  */
3229 static void
3230 uma_startup_pcpu(void *arg __unused)
3231 {
3232 
3233 	zone_foreach_unlocked(zone_alloc_counters, NULL);
3234 	booted = BOOT_PCPU;
3235 }
3236 SYSINIT(uma_startup_pcpu, SI_SUB_COUNTER, SI_ORDER_ANY, uma_startup_pcpu, NULL);
3237 
3238 /*
3239  * Finish our initialization steps.
3240  */
3241 static void
3242 uma_startup3(void *arg __unused)
3243 {
3244 
3245 #ifdef INVARIANTS
3246 	TUNABLE_INT_FETCH("vm.debug.divisor", &dbg_divisor);
3247 	uma_dbg_cnt = counter_u64_alloc(M_WAITOK);
3248 	uma_skip_cnt = counter_u64_alloc(M_WAITOK);
3249 #endif
3250 	zone_foreach_unlocked(zone_alloc_sysctl, NULL);
3251 	booted = BOOT_RUNNING;
3252 
3253 	EVENTHANDLER_REGISTER(shutdown_post_sync, uma_shutdown, NULL,
3254 	    EVENTHANDLER_PRI_FIRST);
3255 }
3256 SYSINIT(uma_startup3, SI_SUB_VM_CONF, SI_ORDER_SECOND, uma_startup3, NULL);
3257 
3258 static void
3259 uma_startup4(void *arg __unused)
3260 {
3261 	TIMEOUT_TASK_INIT(taskqueue_thread, &uma_timeout_task, 0, uma_timeout,
3262 	    NULL);
3263 	taskqueue_enqueue_timeout(taskqueue_thread, &uma_timeout_task,
3264 	    UMA_TIMEOUT * hz);
3265 }
3266 SYSINIT(uma_startup4, SI_SUB_TASKQ, SI_ORDER_ANY, uma_startup4, NULL);
3267 
3268 static void
3269 uma_shutdown(void)
3270 {
3271 
3272 	booted = BOOT_SHUTDOWN;
3273 }
3274 
3275 static uma_keg_t
3276 uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini,
3277 		int align, uint32_t flags)
3278 {
3279 	struct uma_kctor_args args;
3280 
3281 	args.size = size;
3282 	args.uminit = uminit;
3283 	args.fini = fini;
3284 	args.align = align;
3285 	args.flags = flags;
3286 	args.zone = zone;
3287 	return (zone_alloc_item(kegs, &args, UMA_ANYDOMAIN, M_WAITOK));
3288 }
3289 
3290 
3291 static void
3292 check_align_mask(unsigned int mask)
3293 {
3294 
3295 	KASSERT(powerof2(mask + 1),
3296 	    ("UMA: %s: Not the mask of a power of 2 (%#x)", __func__, mask));
3297 	/*
3298 	 * Make sure the stored align mask doesn't have its highest bit set,
3299 	 * which would cause implementation-defined behavior when passing it as
3300 	 * the 'align' argument of uma_zcreate().  Such very large alignments do
3301 	 * not make sense anyway.
3302 	 */
3303 	KASSERT(mask <= INT_MAX,
3304 	    ("UMA: %s: Mask too big (%#x)", __func__, mask));
3305 }
3306 
3307 /* Public functions */
3308 /* See uma.h */
3309 void
3310 uma_set_cache_align_mask(unsigned int mask)
3311 {
3312 
3313 	check_align_mask(mask);
3314 	uma_cache_align_mask = mask;
3315 }
3316 
3317 /* Returns the alignment mask to use to request cache alignment. */
3318 unsigned int
3319 uma_get_cache_align_mask(void)
3320 {
3321 	return (uma_cache_align_mask);
3322 }
3323 
3324 /* See uma.h */
3325 uma_zone_t
3326 uma_zcreate(const char *name, size_t size, uma_ctor ctor, uma_dtor dtor,
3327 		uma_init uminit, uma_fini fini, int align, uint32_t flags)
3328 
3329 {
3330 	struct uma_zctor_args args;
3331 	uma_zone_t res;
3332 
3333 	check_align_mask(align);
3334 
3335 	/* This stuff is essential for the zone ctor */
3336 	memset(&args, 0, sizeof(args));
3337 	args.name = name;
3338 	args.size = size;
3339 	args.ctor = ctor;
3340 	args.dtor = dtor;
3341 	args.uminit = uminit;
3342 	args.fini = fini;
3343 #if defined(INVARIANTS) && !defined(KASAN) && !defined(KMSAN)
3344 	/*
3345 	 * Inject procedures which check for memory use after free if we are
3346 	 * allowed to scramble the memory while it is not allocated.  This
3347 	 * requires that: UMA is actually able to access the memory, no init
3348 	 * or fini procedures, no dependency on the initial value of the
3349 	 * memory, and no (legitimate) use of the memory after free.  Note,
3350 	 * the ctor and dtor do not need to be empty.
3351 	 */
3352 	if ((!(flags & (UMA_ZONE_ZINIT | UMA_ZONE_NOTOUCH |
3353 	    UMA_ZONE_NOFREE))) && uminit == NULL && fini == NULL) {
3354 		args.uminit = trash_init;
3355 		args.fini = trash_fini;
3356 	}
3357 #endif
3358 	args.align = align;
3359 	args.flags = flags;
3360 	args.keg = NULL;
3361 
3362 	sx_xlock(&uma_reclaim_lock);
3363 	res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK);
3364 	sx_xunlock(&uma_reclaim_lock);
3365 
3366 	return (res);
3367 }
3368 
3369 /* See uma.h */
3370 uma_zone_t
3371 uma_zsecond_create(const char *name, uma_ctor ctor, uma_dtor dtor,
3372     uma_init zinit, uma_fini zfini, uma_zone_t primary)
3373 {
3374 	struct uma_zctor_args args;
3375 	uma_keg_t keg;
3376 	uma_zone_t res;
3377 
3378 	keg = primary->uz_keg;
3379 	memset(&args, 0, sizeof(args));
3380 	args.name = name;
3381 	args.size = keg->uk_size;
3382 	args.ctor = ctor;
3383 	args.dtor = dtor;
3384 	args.uminit = zinit;
3385 	args.fini = zfini;
3386 	args.align = keg->uk_align;
3387 	args.flags = keg->uk_flags | UMA_ZONE_SECONDARY;
3388 	args.keg = keg;
3389 
3390 	sx_xlock(&uma_reclaim_lock);
3391 	res = zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK);
3392 	sx_xunlock(&uma_reclaim_lock);
3393 
3394 	return (res);
3395 }
3396 
3397 /* See uma.h */
3398 uma_zone_t
3399 uma_zcache_create(const char *name, int size, uma_ctor ctor, uma_dtor dtor,
3400     uma_init zinit, uma_fini zfini, uma_import zimport, uma_release zrelease,
3401     void *arg, int flags)
3402 {
3403 	struct uma_zctor_args args;
3404 
3405 	memset(&args, 0, sizeof(args));
3406 	args.name = name;
3407 	args.size = size;
3408 	args.ctor = ctor;
3409 	args.dtor = dtor;
3410 	args.uminit = zinit;
3411 	args.fini = zfini;
3412 	args.import = zimport;
3413 	args.release = zrelease;
3414 	args.arg = arg;
3415 	args.align = 0;
3416 	args.flags = flags | UMA_ZFLAG_CACHE;
3417 
3418 	return (zone_alloc_item(zones, &args, UMA_ANYDOMAIN, M_WAITOK));
3419 }
3420 
3421 /* See uma.h */
3422 void
3423 uma_zdestroy(uma_zone_t zone)
3424 {
3425 
3426 	/*
3427 	 * Large slabs are expensive to reclaim, so don't bother doing
3428 	 * unnecessary work if we're shutting down.
3429 	 */
3430 	if (booted == BOOT_SHUTDOWN &&
3431 	    zone->uz_fini == NULL && zone->uz_release == zone_release)
3432 		return;
3433 	sx_xlock(&uma_reclaim_lock);
3434 	zone_free_item(zones, zone, NULL, SKIP_NONE);
3435 	sx_xunlock(&uma_reclaim_lock);
3436 }
3437 
3438 void
3439 uma_zwait(uma_zone_t zone)
3440 {
3441 
3442 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
3443 		uma_zfree_smr(zone, uma_zalloc_smr(zone, M_WAITOK));
3444 	else if ((zone->uz_flags & UMA_ZONE_PCPU) != 0)
3445 		uma_zfree_pcpu(zone, uma_zalloc_pcpu(zone, M_WAITOK));
3446 	else
3447 		uma_zfree(zone, uma_zalloc(zone, M_WAITOK));
3448 }
3449 
3450 void *
3451 uma_zalloc_pcpu_arg(uma_zone_t zone, void *udata, int flags)
3452 {
3453 	void *item, *pcpu_item;
3454 #ifdef SMP
3455 	int i;
3456 
3457 	MPASS(zone->uz_flags & UMA_ZONE_PCPU);
3458 #endif
3459 	item = uma_zalloc_arg(zone, udata, flags & ~M_ZERO);
3460 	if (item == NULL)
3461 		return (NULL);
3462 	pcpu_item = zpcpu_base_to_offset(item);
3463 	if (flags & M_ZERO) {
3464 #ifdef SMP
3465 		for (i = 0; i <= mp_maxid; i++)
3466 			bzero(zpcpu_get_cpu(pcpu_item, i), zone->uz_size);
3467 #else
3468 		bzero(item, zone->uz_size);
3469 #endif
3470 	}
3471 	return (pcpu_item);
3472 }
3473 
3474 /*
3475  * A stub while both regular and pcpu cases are identical.
3476  */
3477 void
3478 uma_zfree_pcpu_arg(uma_zone_t zone, void *pcpu_item, void *udata)
3479 {
3480 	void *item;
3481 
3482 #ifdef SMP
3483 	MPASS(zone->uz_flags & UMA_ZONE_PCPU);
3484 #endif
3485 
3486         /* uma_zfree_pcu_*(..., NULL) does nothing, to match free(9). */
3487         if (pcpu_item == NULL)
3488                 return;
3489 
3490 	item = zpcpu_offset_to_base(pcpu_item);
3491 	uma_zfree_arg(zone, item, udata);
3492 }
3493 
3494 static inline void *
3495 item_ctor(uma_zone_t zone, int uz_flags, int size, void *udata, int flags,
3496     void *item)
3497 {
3498 #ifdef INVARIANTS
3499 	bool skipdbg;
3500 #endif
3501 
3502 	kasan_mark_item_valid(zone, item);
3503 	kmsan_mark_item_uninitialized(zone, item);
3504 
3505 #ifdef INVARIANTS
3506 	skipdbg = uma_dbg_zskip(zone, item);
3507 	if (!skipdbg && (uz_flags & UMA_ZFLAG_TRASH) != 0 &&
3508 	    zone->uz_ctor != trash_ctor)
3509 		trash_ctor(item, size, zone, flags);
3510 #endif
3511 
3512 	/* Check flags before loading ctor pointer. */
3513 	if (__predict_false((uz_flags & UMA_ZFLAG_CTORDTOR) != 0) &&
3514 	    __predict_false(zone->uz_ctor != NULL) &&
3515 	    zone->uz_ctor(item, size, udata, flags) != 0) {
3516 		counter_u64_add(zone->uz_fails, 1);
3517 		zone_free_item(zone, item, udata, SKIP_DTOR | SKIP_CNT);
3518 		return (NULL);
3519 	}
3520 #ifdef INVARIANTS
3521 	if (!skipdbg)
3522 		uma_dbg_alloc(zone, NULL, item);
3523 #endif
3524 	if (__predict_false(flags & M_ZERO))
3525 		return (memset(item, 0, size));
3526 
3527 	return (item);
3528 }
3529 
3530 static inline void
3531 item_dtor(uma_zone_t zone, void *item, int size, void *udata,
3532     enum zfreeskip skip)
3533 {
3534 #ifdef INVARIANTS
3535 	bool skipdbg;
3536 
3537 	skipdbg = uma_dbg_zskip(zone, item);
3538 	if (skip == SKIP_NONE && !skipdbg) {
3539 		if ((zone->uz_flags & UMA_ZONE_MALLOC) != 0)
3540 			uma_dbg_free(zone, udata, item);
3541 		else
3542 			uma_dbg_free(zone, NULL, item);
3543 	}
3544 #endif
3545 	if (__predict_true(skip < SKIP_DTOR)) {
3546 		if (zone->uz_dtor != NULL)
3547 			zone->uz_dtor(item, size, udata);
3548 #ifdef INVARIANTS
3549 		if (!skipdbg && (zone->uz_flags & UMA_ZFLAG_TRASH) != 0 &&
3550 		    zone->uz_dtor != trash_dtor)
3551 			trash_dtor(item, size, zone);
3552 #endif
3553 	}
3554 	kasan_mark_item_invalid(zone, item);
3555 }
3556 
3557 #ifdef NUMA
3558 static int
3559 item_domain(void *item)
3560 {
3561 	int domain;
3562 
3563 	domain = vm_phys_domain(vtophys(item));
3564 	KASSERT(domain >= 0 && domain < vm_ndomains,
3565 	    ("%s: unknown domain for item %p", __func__, item));
3566 	return (domain);
3567 }
3568 #endif
3569 
3570 #if defined(INVARIANTS) || defined(DEBUG_MEMGUARD) || defined(WITNESS)
3571 #if defined(INVARIANTS) && (defined(DDB) || defined(STACK))
3572 #include <sys/stack.h>
3573 #endif
3574 #define	UMA_ZALLOC_DEBUG
3575 static int
3576 uma_zalloc_debug(uma_zone_t zone, void **itemp, void *udata, int flags)
3577 {
3578 	int error;
3579 
3580 	error = 0;
3581 #ifdef WITNESS
3582 	if (flags & M_WAITOK) {
3583 		WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
3584 		    "uma_zalloc_debug: zone \"%s\"", zone->uz_name);
3585 	}
3586 #endif
3587 
3588 #ifdef INVARIANTS
3589 	KASSERT((flags & M_EXEC) == 0,
3590 	    ("uma_zalloc_debug: called with M_EXEC"));
3591 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
3592 	    ("uma_zalloc_debug: called within spinlock or critical section"));
3593 	KASSERT((zone->uz_flags & UMA_ZONE_PCPU) == 0 || (flags & M_ZERO) == 0,
3594 	    ("uma_zalloc_debug: allocating from a pcpu zone with M_ZERO"));
3595 
3596 	_Static_assert(M_NOWAIT != 0 && M_WAITOK != 0,
3597 	    "M_NOWAIT and M_WAITOK must be non-zero for this assertion:");
3598 #if 0
3599 	/*
3600 	 * Give the #elif clause time to find problems, then remove it
3601 	 * and enable this.  (Remove <sys/stack.h> above, too.)
3602 	 */
3603 	KASSERT((flags & (M_NOWAIT|M_WAITOK)) == M_NOWAIT ||
3604 	    (flags & (M_NOWAIT|M_WAITOK)) == M_WAITOK,
3605 	    ("uma_zalloc_debug: must pass one of M_NOWAIT or M_WAITOK"));
3606 #elif defined(DDB) || defined(STACK)
3607 	if (__predict_false((flags & (M_NOWAIT|M_WAITOK)) != M_NOWAIT &&
3608 	    (flags & (M_NOWAIT|M_WAITOK)) != M_WAITOK)) {
3609 		static int stack_count;
3610 		struct stack st;
3611 
3612 		if (stack_count < 10) {
3613 			++stack_count;
3614 			printf("uma_zalloc* called with bad WAIT flags:\n");
3615 			stack_save(&st);
3616 			stack_print(&st);
3617 		}
3618 	}
3619 #endif
3620 #endif
3621 
3622 #ifdef DEBUG_MEMGUARD
3623 	if ((zone->uz_flags & (UMA_ZONE_SMR | UMA_ZFLAG_CACHE)) == 0 &&
3624 	    memguard_cmp_zone(zone)) {
3625 		void *item;
3626 		item = memguard_alloc(zone->uz_size, flags);
3627 		if (item != NULL) {
3628 			error = EJUSTRETURN;
3629 			if (zone->uz_init != NULL &&
3630 			    zone->uz_init(item, zone->uz_size, flags) != 0) {
3631 				*itemp = NULL;
3632 				return (error);
3633 			}
3634 			if (zone->uz_ctor != NULL &&
3635 			    zone->uz_ctor(item, zone->uz_size, udata,
3636 			    flags) != 0) {
3637 				counter_u64_add(zone->uz_fails, 1);
3638 				if (zone->uz_fini != NULL)
3639 					zone->uz_fini(item, zone->uz_size);
3640 				*itemp = NULL;
3641 				return (error);
3642 			}
3643 			*itemp = item;
3644 			return (error);
3645 		}
3646 		/* This is unfortunate but should not be fatal. */
3647 	}
3648 #endif
3649 	return (error);
3650 }
3651 
3652 static int
3653 uma_zfree_debug(uma_zone_t zone, void *item, void *udata)
3654 {
3655 	KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
3656 	    ("uma_zfree_debug: called with spinlock or critical section held"));
3657 
3658 #ifdef DEBUG_MEMGUARD
3659 	if ((zone->uz_flags & (UMA_ZONE_SMR | UMA_ZFLAG_CACHE)) == 0 &&
3660 	    is_memguard_addr(item)) {
3661 		if (zone->uz_dtor != NULL)
3662 			zone->uz_dtor(item, zone->uz_size, udata);
3663 		if (zone->uz_fini != NULL)
3664 			zone->uz_fini(item, zone->uz_size);
3665 		memguard_free(item);
3666 		return (EJUSTRETURN);
3667 	}
3668 #endif
3669 	return (0);
3670 }
3671 #endif
3672 
3673 static inline void *
3674 cache_alloc_item(uma_zone_t zone, uma_cache_t cache, uma_cache_bucket_t bucket,
3675     void *udata, int flags)
3676 {
3677 	void *item;
3678 	int size, uz_flags;
3679 
3680 	item = cache_bucket_pop(cache, bucket);
3681 	size = cache_uz_size(cache);
3682 	uz_flags = cache_uz_flags(cache);
3683 	critical_exit();
3684 	return (item_ctor(zone, uz_flags, size, udata, flags, item));
3685 }
3686 
3687 static __noinline void *
3688 cache_alloc_retry(uma_zone_t zone, uma_cache_t cache, void *udata, int flags)
3689 {
3690 	uma_cache_bucket_t bucket;
3691 	int domain;
3692 
3693 	while (cache_alloc(zone, cache, udata, flags)) {
3694 		cache = &zone->uz_cpu[curcpu];
3695 		bucket = &cache->uc_allocbucket;
3696 		if (__predict_false(bucket->ucb_cnt == 0))
3697 			continue;
3698 		return (cache_alloc_item(zone, cache, bucket, udata, flags));
3699 	}
3700 	critical_exit();
3701 
3702 	/*
3703 	 * We can not get a bucket so try to return a single item.
3704 	 */
3705 	if (zone->uz_flags & UMA_ZONE_FIRSTTOUCH)
3706 		domain = PCPU_GET(domain);
3707 	else
3708 		domain = UMA_ANYDOMAIN;
3709 	return (zone_alloc_item(zone, udata, domain, flags));
3710 }
3711 
3712 /* See uma.h */
3713 void *
3714 uma_zalloc_smr(uma_zone_t zone, int flags)
3715 {
3716 	uma_cache_bucket_t bucket;
3717 	uma_cache_t cache;
3718 
3719 	CTR3(KTR_UMA, "uma_zalloc_smr zone %s(%p) flags %d", zone->uz_name,
3720 	    zone, flags);
3721 
3722 #ifdef UMA_ZALLOC_DEBUG
3723 	void *item;
3724 
3725 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) != 0,
3726 	    ("uma_zalloc_arg: called with non-SMR zone."));
3727 	if (uma_zalloc_debug(zone, &item, NULL, flags) == EJUSTRETURN)
3728 		return (item);
3729 #endif
3730 
3731 	critical_enter();
3732 	cache = &zone->uz_cpu[curcpu];
3733 	bucket = &cache->uc_allocbucket;
3734 	if (__predict_false(bucket->ucb_cnt == 0))
3735 		return (cache_alloc_retry(zone, cache, NULL, flags));
3736 	return (cache_alloc_item(zone, cache, bucket, NULL, flags));
3737 }
3738 
3739 /* See uma.h */
3740 void *
3741 uma_zalloc_arg(uma_zone_t zone, void *udata, int flags)
3742 {
3743 	uma_cache_bucket_t bucket;
3744 	uma_cache_t cache;
3745 
3746 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
3747 	random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
3748 
3749 	/* This is the fast path allocation */
3750 	CTR3(KTR_UMA, "uma_zalloc_arg zone %s(%p) flags %d", zone->uz_name,
3751 	    zone, flags);
3752 
3753 #ifdef UMA_ZALLOC_DEBUG
3754 	void *item;
3755 
3756 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
3757 	    ("uma_zalloc_arg: called with SMR zone."));
3758 	if (uma_zalloc_debug(zone, &item, udata, flags) == EJUSTRETURN)
3759 		return (item);
3760 #endif
3761 
3762 	/*
3763 	 * If possible, allocate from the per-CPU cache.  There are two
3764 	 * requirements for safe access to the per-CPU cache: (1) the thread
3765 	 * accessing the cache must not be preempted or yield during access,
3766 	 * and (2) the thread must not migrate CPUs without switching which
3767 	 * cache it accesses.  We rely on a critical section to prevent
3768 	 * preemption and migration.  We release the critical section in
3769 	 * order to acquire the zone mutex if we are unable to allocate from
3770 	 * the current cache; when we re-acquire the critical section, we
3771 	 * must detect and handle migration if it has occurred.
3772 	 */
3773 	critical_enter();
3774 	cache = &zone->uz_cpu[curcpu];
3775 	bucket = &cache->uc_allocbucket;
3776 	if (__predict_false(bucket->ucb_cnt == 0))
3777 		return (cache_alloc_retry(zone, cache, udata, flags));
3778 	return (cache_alloc_item(zone, cache, bucket, udata, flags));
3779 }
3780 
3781 /*
3782  * Replenish an alloc bucket and possibly restore an old one.  Called in
3783  * a critical section.  Returns in a critical section.
3784  *
3785  * A false return value indicates an allocation failure.
3786  * A true return value indicates success and the caller should retry.
3787  */
3788 static __noinline bool
3789 cache_alloc(uma_zone_t zone, uma_cache_t cache, void *udata, int flags)
3790 {
3791 	uma_bucket_t bucket;
3792 	int curdomain, domain;
3793 	bool new;
3794 
3795 	CRITICAL_ASSERT(curthread);
3796 
3797 	/*
3798 	 * If we have run out of items in our alloc bucket see
3799 	 * if we can switch with the free bucket.
3800 	 *
3801 	 * SMR Zones can't re-use the free bucket until the sequence has
3802 	 * expired.
3803 	 */
3804 	if ((cache_uz_flags(cache) & UMA_ZONE_SMR) == 0 &&
3805 	    cache->uc_freebucket.ucb_cnt != 0) {
3806 		cache_bucket_swap(&cache->uc_freebucket,
3807 		    &cache->uc_allocbucket);
3808 		return (true);
3809 	}
3810 
3811 	/*
3812 	 * Discard any empty allocation bucket while we hold no locks.
3813 	 */
3814 	bucket = cache_bucket_unload_alloc(cache);
3815 	critical_exit();
3816 
3817 	if (bucket != NULL) {
3818 		KASSERT(bucket->ub_cnt == 0,
3819 		    ("cache_alloc: Entered with non-empty alloc bucket."));
3820 		bucket_free(zone, bucket, udata);
3821 	}
3822 
3823 	/*
3824 	 * Attempt to retrieve the item from the per-CPU cache has failed, so
3825 	 * we must go back to the zone.  This requires the zdom lock, so we
3826 	 * must drop the critical section, then re-acquire it when we go back
3827 	 * to the cache.  Since the critical section is released, we may be
3828 	 * preempted or migrate.  As such, make sure not to maintain any
3829 	 * thread-local state specific to the cache from prior to releasing
3830 	 * the critical section.
3831 	 */
3832 	domain = PCPU_GET(domain);
3833 	if ((cache_uz_flags(cache) & UMA_ZONE_ROUNDROBIN) != 0 ||
3834 	    VM_DOMAIN_EMPTY(domain))
3835 		domain = zone_domain_highest(zone, domain);
3836 	bucket = cache_fetch_bucket(zone, cache, domain);
3837 	if (bucket == NULL && zone->uz_bucket_size != 0 && !bucketdisable) {
3838 		bucket = zone_alloc_bucket(zone, udata, domain, flags);
3839 		new = true;
3840 	} else {
3841 		new = false;
3842 	}
3843 
3844 	CTR3(KTR_UMA, "uma_zalloc: zone %s(%p) bucket zone returned %p",
3845 	    zone->uz_name, zone, bucket);
3846 	if (bucket == NULL) {
3847 		critical_enter();
3848 		return (false);
3849 	}
3850 
3851 	/*
3852 	 * See if we lost the race or were migrated.  Cache the
3853 	 * initialized bucket to make this less likely or claim
3854 	 * the memory directly.
3855 	 */
3856 	critical_enter();
3857 	cache = &zone->uz_cpu[curcpu];
3858 	if (cache->uc_allocbucket.ucb_bucket == NULL &&
3859 	    ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) == 0 ||
3860 	    (curdomain = PCPU_GET(domain)) == domain ||
3861 	    VM_DOMAIN_EMPTY(curdomain))) {
3862 		if (new)
3863 			atomic_add_long(&ZDOM_GET(zone, domain)->uzd_imax,
3864 			    bucket->ub_cnt);
3865 		cache_bucket_load_alloc(cache, bucket);
3866 		return (true);
3867 	}
3868 
3869 	/*
3870 	 * We lost the race, release this bucket and start over.
3871 	 */
3872 	critical_exit();
3873 	zone_put_bucket(zone, domain, bucket, udata, !new);
3874 	critical_enter();
3875 
3876 	return (true);
3877 }
3878 
3879 void *
3880 uma_zalloc_domain(uma_zone_t zone, void *udata, int domain, int flags)
3881 {
3882 #ifdef NUMA
3883 	uma_bucket_t bucket;
3884 	uma_zone_domain_t zdom;
3885 	void *item;
3886 #endif
3887 
3888 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
3889 	random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
3890 
3891 	/* This is the fast path allocation */
3892 	CTR4(KTR_UMA, "uma_zalloc_domain zone %s(%p) domain %d flags %d",
3893 	    zone->uz_name, zone, domain, flags);
3894 
3895 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
3896 	    ("uma_zalloc_domain: called with SMR zone."));
3897 #ifdef NUMA
3898 	KASSERT((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0,
3899 	    ("uma_zalloc_domain: called with non-FIRSTTOUCH zone."));
3900 
3901 	if (vm_ndomains == 1)
3902 		return (uma_zalloc_arg(zone, udata, flags));
3903 
3904 #ifdef UMA_ZALLOC_DEBUG
3905 	if (uma_zalloc_debug(zone, &item, udata, flags) == EJUSTRETURN)
3906 		return (item);
3907 #endif
3908 
3909 	/*
3910 	 * Try to allocate from the bucket cache before falling back to the keg.
3911 	 * We could try harder and attempt to allocate from per-CPU caches or
3912 	 * the per-domain cross-domain buckets, but the complexity is probably
3913 	 * not worth it.  It is more important that frees of previous
3914 	 * cross-domain allocations do not blow up the cache.
3915 	 */
3916 	zdom = zone_domain_lock(zone, domain);
3917 	if ((bucket = zone_fetch_bucket(zone, zdom, false)) != NULL) {
3918 		item = bucket->ub_bucket[bucket->ub_cnt - 1];
3919 #ifdef INVARIANTS
3920 		bucket->ub_bucket[bucket->ub_cnt - 1] = NULL;
3921 #endif
3922 		bucket->ub_cnt--;
3923 		zone_put_bucket(zone, domain, bucket, udata, true);
3924 		item = item_ctor(zone, zone->uz_flags, zone->uz_size, udata,
3925 		    flags, item);
3926 		if (item != NULL) {
3927 			KASSERT(item_domain(item) == domain,
3928 			    ("%s: bucket cache item %p from wrong domain",
3929 			    __func__, item));
3930 			counter_u64_add(zone->uz_allocs, 1);
3931 		}
3932 		return (item);
3933 	}
3934 	ZDOM_UNLOCK(zdom);
3935 	return (zone_alloc_item(zone, udata, domain, flags));
3936 #else
3937 	return (uma_zalloc_arg(zone, udata, flags));
3938 #endif
3939 }
3940 
3941 /*
3942  * Find a slab with some space.  Prefer slabs that are partially used over those
3943  * that are totally full.  This helps to reduce fragmentation.
3944  *
3945  * If 'rr' is 1, search all domains starting from 'domain'.  Otherwise check
3946  * only 'domain'.
3947  */
3948 static uma_slab_t
3949 keg_first_slab(uma_keg_t keg, int domain, bool rr)
3950 {
3951 	uma_domain_t dom;
3952 	uma_slab_t slab;
3953 	int start;
3954 
3955 	KASSERT(domain >= 0 && domain < vm_ndomains,
3956 	    ("keg_first_slab: domain %d out of range", domain));
3957 	KEG_LOCK_ASSERT(keg, domain);
3958 
3959 	slab = NULL;
3960 	start = domain;
3961 	do {
3962 		dom = &keg->uk_domain[domain];
3963 		if ((slab = LIST_FIRST(&dom->ud_part_slab)) != NULL)
3964 			return (slab);
3965 		if ((slab = LIST_FIRST(&dom->ud_free_slab)) != NULL) {
3966 			LIST_REMOVE(slab, us_link);
3967 			dom->ud_free_slabs--;
3968 			LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
3969 			return (slab);
3970 		}
3971 		if (rr)
3972 			domain = (domain + 1) % vm_ndomains;
3973 	} while (domain != start);
3974 
3975 	return (NULL);
3976 }
3977 
3978 /*
3979  * Fetch an existing slab from a free or partial list.  Returns with the
3980  * keg domain lock held if a slab was found or unlocked if not.
3981  */
3982 static uma_slab_t
3983 keg_fetch_free_slab(uma_keg_t keg, int domain, bool rr, int flags)
3984 {
3985 	uma_slab_t slab;
3986 	uint32_t reserve;
3987 
3988 	/* HASH has a single free list. */
3989 	if ((keg->uk_flags & UMA_ZFLAG_HASH) != 0)
3990 		domain = 0;
3991 
3992 	KEG_LOCK(keg, domain);
3993 	reserve = (flags & M_USE_RESERVE) != 0 ? 0 : keg->uk_reserve;
3994 	if (keg->uk_domain[domain].ud_free_items <= reserve ||
3995 	    (slab = keg_first_slab(keg, domain, rr)) == NULL) {
3996 		KEG_UNLOCK(keg, domain);
3997 		return (NULL);
3998 	}
3999 	return (slab);
4000 }
4001 
4002 static uma_slab_t
4003 keg_fetch_slab(uma_keg_t keg, uma_zone_t zone, int rdomain, const int flags)
4004 {
4005 	struct vm_domainset_iter di;
4006 	uma_slab_t slab;
4007 	int aflags, domain;
4008 	bool rr;
4009 
4010 	KASSERT((flags & (M_WAITOK | M_NOVM)) != (M_WAITOK | M_NOVM),
4011 	    ("%s: invalid flags %#x", __func__, flags));
4012 
4013 restart:
4014 	/*
4015 	 * Use the keg's policy if upper layers haven't already specified a
4016 	 * domain (as happens with first-touch zones).
4017 	 *
4018 	 * To avoid races we run the iterator with the keg lock held, but that
4019 	 * means that we cannot allow the vm_domainset layer to sleep.  Thus,
4020 	 * clear M_WAITOK and handle low memory conditions locally.
4021 	 */
4022 	rr = rdomain == UMA_ANYDOMAIN;
4023 	if (rr) {
4024 		aflags = (flags & ~M_WAITOK) | M_NOWAIT;
4025 		vm_domainset_iter_policy_ref_init(&di, &keg->uk_dr, &domain,
4026 		    &aflags);
4027 	} else {
4028 		aflags = flags;
4029 		domain = rdomain;
4030 	}
4031 
4032 	for (;;) {
4033 		slab = keg_fetch_free_slab(keg, domain, rr, flags);
4034 		if (slab != NULL)
4035 			return (slab);
4036 
4037 		/*
4038 		 * M_NOVM is used to break the recursion that can otherwise
4039 		 * occur if low-level memory management routines use UMA.
4040 		 */
4041 		if ((flags & M_NOVM) == 0) {
4042 			slab = keg_alloc_slab(keg, zone, domain, flags, aflags);
4043 			if (slab != NULL)
4044 				return (slab);
4045 		}
4046 
4047 		if (!rr) {
4048 			if ((flags & M_USE_RESERVE) != 0) {
4049 				/*
4050 				 * Drain reserves from other domains before
4051 				 * giving up or sleeping.  It may be useful to
4052 				 * support per-domain reserves eventually.
4053 				 */
4054 				rdomain = UMA_ANYDOMAIN;
4055 				goto restart;
4056 			}
4057 			if ((flags & M_WAITOK) == 0)
4058 				break;
4059 			vm_wait_domain(domain);
4060 		} else if (vm_domainset_iter_policy(&di, &domain) != 0) {
4061 			if ((flags & M_WAITOK) != 0) {
4062 				vm_wait_doms(&keg->uk_dr.dr_policy->ds_mask, 0);
4063 				goto restart;
4064 			}
4065 			break;
4066 		}
4067 	}
4068 
4069 	/*
4070 	 * We might not have been able to get a slab but another cpu
4071 	 * could have while we were unlocked.  Check again before we
4072 	 * fail.
4073 	 */
4074 	if ((slab = keg_fetch_free_slab(keg, domain, rr, flags)) != NULL)
4075 		return (slab);
4076 
4077 	return (NULL);
4078 }
4079 
4080 static void *
4081 slab_alloc_item(uma_keg_t keg, uma_slab_t slab)
4082 {
4083 	uma_domain_t dom;
4084 	void *item;
4085 	int freei;
4086 
4087 	KEG_LOCK_ASSERT(keg, slab->us_domain);
4088 
4089 	dom = &keg->uk_domain[slab->us_domain];
4090 	freei = BIT_FFS(keg->uk_ipers, &slab->us_free) - 1;
4091 	BIT_CLR(keg->uk_ipers, freei, &slab->us_free);
4092 	item = slab_item(slab, keg, freei);
4093 	slab->us_freecount--;
4094 	dom->ud_free_items--;
4095 
4096 	/*
4097 	 * Move this slab to the full list.  It must be on the partial list, so
4098 	 * we do not need to update the free slab count.  In particular,
4099 	 * keg_fetch_slab() always returns slabs on the partial list.
4100 	 */
4101 	if (slab->us_freecount == 0) {
4102 		LIST_REMOVE(slab, us_link);
4103 		LIST_INSERT_HEAD(&dom->ud_full_slab, slab, us_link);
4104 	}
4105 
4106 	return (item);
4107 }
4108 
4109 static int
4110 zone_import(void *arg, void **bucket, int max, int domain, int flags)
4111 {
4112 	uma_domain_t dom;
4113 	uma_zone_t zone;
4114 	uma_slab_t slab;
4115 	uma_keg_t keg;
4116 #ifdef NUMA
4117 	int stripe;
4118 #endif
4119 	int i;
4120 
4121 	zone = arg;
4122 	slab = NULL;
4123 	keg = zone->uz_keg;
4124 	/* Try to keep the buckets totally full */
4125 	for (i = 0; i < max; ) {
4126 		if ((slab = keg_fetch_slab(keg, zone, domain, flags)) == NULL)
4127 			break;
4128 #ifdef NUMA
4129 		stripe = howmany(max, vm_ndomains);
4130 #endif
4131 		dom = &keg->uk_domain[slab->us_domain];
4132 		do {
4133 			bucket[i++] = slab_alloc_item(keg, slab);
4134 			if (keg->uk_reserve > 0 &&
4135 			    dom->ud_free_items <= keg->uk_reserve) {
4136 				/*
4137 				 * Avoid depleting the reserve after a
4138 				 * successful item allocation, even if
4139 				 * M_USE_RESERVE is specified.
4140 				 */
4141 				KEG_UNLOCK(keg, slab->us_domain);
4142 				goto out;
4143 			}
4144 #ifdef NUMA
4145 			/*
4146 			 * If the zone is striped we pick a new slab for every
4147 			 * N allocations.  Eliminating this conditional will
4148 			 * instead pick a new domain for each bucket rather
4149 			 * than stripe within each bucket.  The current option
4150 			 * produces more fragmentation and requires more cpu
4151 			 * time but yields better distribution.
4152 			 */
4153 			if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0 &&
4154 			    vm_ndomains > 1 && --stripe == 0)
4155 				break;
4156 #endif
4157 		} while (slab->us_freecount != 0 && i < max);
4158 		KEG_UNLOCK(keg, slab->us_domain);
4159 
4160 		/* Don't block if we allocated any successfully. */
4161 		flags &= ~M_WAITOK;
4162 		flags |= M_NOWAIT;
4163 	}
4164 out:
4165 	return i;
4166 }
4167 
4168 static int
4169 zone_alloc_limit_hard(uma_zone_t zone, int count, int flags)
4170 {
4171 	uint64_t old, new, total, max;
4172 
4173 	/*
4174 	 * The hard case.  We're going to sleep because there were existing
4175 	 * sleepers or because we ran out of items.  This routine enforces
4176 	 * fairness by keeping fifo order.
4177 	 *
4178 	 * First release our ill gotten gains and make some noise.
4179 	 */
4180 	for (;;) {
4181 		zone_free_limit(zone, count);
4182 		zone_log_warning(zone);
4183 		zone_maxaction(zone);
4184 		if (flags & M_NOWAIT)
4185 			return (0);
4186 
4187 		/*
4188 		 * We need to allocate an item or set ourself as a sleeper
4189 		 * while the sleepq lock is held to avoid wakeup races.  This
4190 		 * is essentially a home rolled semaphore.
4191 		 */
4192 		sleepq_lock(&zone->uz_max_items);
4193 		old = zone->uz_items;
4194 		do {
4195 			MPASS(UZ_ITEMS_SLEEPERS(old) < UZ_ITEMS_SLEEPERS_MAX);
4196 			/* Cache the max since we will evaluate twice. */
4197 			max = zone->uz_max_items;
4198 			if (UZ_ITEMS_SLEEPERS(old) != 0 ||
4199 			    UZ_ITEMS_COUNT(old) >= max)
4200 				new = old + UZ_ITEMS_SLEEPER;
4201 			else
4202 				new = old + MIN(count, max - old);
4203 		} while (atomic_fcmpset_64(&zone->uz_items, &old, new) == 0);
4204 
4205 		/* We may have successfully allocated under the sleepq lock. */
4206 		if (UZ_ITEMS_SLEEPERS(new) == 0) {
4207 			sleepq_release(&zone->uz_max_items);
4208 			return (new - old);
4209 		}
4210 
4211 		/*
4212 		 * This is in a different cacheline from uz_items so that we
4213 		 * don't constantly invalidate the fastpath cacheline when we
4214 		 * adjust item counts.  This could be limited to toggling on
4215 		 * transitions.
4216 		 */
4217 		atomic_add_32(&zone->uz_sleepers, 1);
4218 		atomic_add_64(&zone->uz_sleeps, 1);
4219 
4220 		/*
4221 		 * We have added ourselves as a sleeper.  The sleepq lock
4222 		 * protects us from wakeup races.  Sleep now and then retry.
4223 		 */
4224 		sleepq_add(&zone->uz_max_items, NULL, "zonelimit", 0, 0);
4225 		sleepq_wait(&zone->uz_max_items, PVM);
4226 
4227 		/*
4228 		 * After wakeup, remove ourselves as a sleeper and try
4229 		 * again.  We no longer have the sleepq lock for protection.
4230 		 *
4231 		 * Subract ourselves as a sleeper while attempting to add
4232 		 * our count.
4233 		 */
4234 		atomic_subtract_32(&zone->uz_sleepers, 1);
4235 		old = atomic_fetchadd_64(&zone->uz_items,
4236 		    -(UZ_ITEMS_SLEEPER - count));
4237 		/* We're no longer a sleeper. */
4238 		old -= UZ_ITEMS_SLEEPER;
4239 
4240 		/*
4241 		 * If we're still at the limit, restart.  Notably do not
4242 		 * block on other sleepers.  Cache the max value to protect
4243 		 * against changes via sysctl.
4244 		 */
4245 		total = UZ_ITEMS_COUNT(old);
4246 		max = zone->uz_max_items;
4247 		if (total >= max)
4248 			continue;
4249 		/* Truncate if necessary, otherwise wake other sleepers. */
4250 		if (total + count > max) {
4251 			zone_free_limit(zone, total + count - max);
4252 			count = max - total;
4253 		} else if (total + count < max && UZ_ITEMS_SLEEPERS(old) != 0)
4254 			wakeup_one(&zone->uz_max_items);
4255 
4256 		return (count);
4257 	}
4258 }
4259 
4260 /*
4261  * Allocate 'count' items from our max_items limit.  Returns the number
4262  * available.  If M_NOWAIT is not specified it will sleep until at least
4263  * one item can be allocated.
4264  */
4265 static int
4266 zone_alloc_limit(uma_zone_t zone, int count, int flags)
4267 {
4268 	uint64_t old;
4269 	uint64_t max;
4270 
4271 	max = zone->uz_max_items;
4272 	MPASS(max > 0);
4273 
4274 	/*
4275 	 * We expect normal allocations to succeed with a simple
4276 	 * fetchadd.
4277 	 */
4278 	old = atomic_fetchadd_64(&zone->uz_items, count);
4279 	if (__predict_true(old + count <= max))
4280 		return (count);
4281 
4282 	/*
4283 	 * If we had some items and no sleepers just return the
4284 	 * truncated value.  We have to release the excess space
4285 	 * though because that may wake sleepers who weren't woken
4286 	 * because we were temporarily over the limit.
4287 	 */
4288 	if (old < max) {
4289 		zone_free_limit(zone, (old + count) - max);
4290 		return (max - old);
4291 	}
4292 	return (zone_alloc_limit_hard(zone, count, flags));
4293 }
4294 
4295 /*
4296  * Free a number of items back to the limit.
4297  */
4298 static void
4299 zone_free_limit(uma_zone_t zone, int count)
4300 {
4301 	uint64_t old;
4302 
4303 	MPASS(count > 0);
4304 
4305 	/*
4306 	 * In the common case we either have no sleepers or
4307 	 * are still over the limit and can just return.
4308 	 */
4309 	old = atomic_fetchadd_64(&zone->uz_items, -count);
4310 	if (__predict_true(UZ_ITEMS_SLEEPERS(old) == 0 ||
4311 	   UZ_ITEMS_COUNT(old) - count >= zone->uz_max_items))
4312 		return;
4313 
4314 	/*
4315 	 * Moderate the rate of wakeups.  Sleepers will continue
4316 	 * to generate wakeups if necessary.
4317 	 */
4318 	wakeup_one(&zone->uz_max_items);
4319 }
4320 
4321 static uma_bucket_t
4322 zone_alloc_bucket(uma_zone_t zone, void *udata, int domain, int flags)
4323 {
4324 	uma_bucket_t bucket;
4325 	int error, maxbucket, cnt;
4326 
4327 	CTR3(KTR_UMA, "zone_alloc_bucket zone %s(%p) domain %d", zone->uz_name,
4328 	    zone, domain);
4329 
4330 	/* Avoid allocs targeting empty domains. */
4331 	if (domain != UMA_ANYDOMAIN && VM_DOMAIN_EMPTY(domain))
4332 		domain = UMA_ANYDOMAIN;
4333 	else if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0)
4334 		domain = UMA_ANYDOMAIN;
4335 
4336 	if (zone->uz_max_items > 0)
4337 		maxbucket = zone_alloc_limit(zone, zone->uz_bucket_size,
4338 		    M_NOWAIT);
4339 	else
4340 		maxbucket = zone->uz_bucket_size;
4341 	if (maxbucket == 0)
4342 		return (NULL);
4343 
4344 	/* Don't wait for buckets, preserve caller's NOVM setting. */
4345 	bucket = bucket_alloc(zone, udata, M_NOWAIT | (flags & M_NOVM));
4346 	if (bucket == NULL) {
4347 		cnt = 0;
4348 		goto out;
4349 	}
4350 
4351 	bucket->ub_cnt = zone->uz_import(zone->uz_arg, bucket->ub_bucket,
4352 	    MIN(maxbucket, bucket->ub_entries), domain, flags);
4353 
4354 	/*
4355 	 * Initialize the memory if necessary.
4356 	 */
4357 	if (bucket->ub_cnt != 0 && zone->uz_init != NULL) {
4358 		int i;
4359 
4360 		for (i = 0; i < bucket->ub_cnt; i++) {
4361 			kasan_mark_item_valid(zone, bucket->ub_bucket[i]);
4362 			error = zone->uz_init(bucket->ub_bucket[i],
4363 			    zone->uz_size, flags);
4364 			kasan_mark_item_invalid(zone, bucket->ub_bucket[i]);
4365 			if (error != 0)
4366 				break;
4367 		}
4368 
4369 		/*
4370 		 * If we couldn't initialize the whole bucket, put the
4371 		 * rest back onto the freelist.
4372 		 */
4373 		if (i != bucket->ub_cnt) {
4374 			zone->uz_release(zone->uz_arg, &bucket->ub_bucket[i],
4375 			    bucket->ub_cnt - i);
4376 #ifdef INVARIANTS
4377 			bzero(&bucket->ub_bucket[i],
4378 			    sizeof(void *) * (bucket->ub_cnt - i));
4379 #endif
4380 			bucket->ub_cnt = i;
4381 		}
4382 	}
4383 
4384 	cnt = bucket->ub_cnt;
4385 	if (bucket->ub_cnt == 0) {
4386 		bucket_free(zone, bucket, udata);
4387 		counter_u64_add(zone->uz_fails, 1);
4388 		bucket = NULL;
4389 	}
4390 out:
4391 	if (zone->uz_max_items > 0 && cnt < maxbucket)
4392 		zone_free_limit(zone, maxbucket - cnt);
4393 
4394 	return (bucket);
4395 }
4396 
4397 /*
4398  * Allocates a single item from a zone.
4399  *
4400  * Arguments
4401  *	zone   The zone to alloc for.
4402  *	udata  The data to be passed to the constructor.
4403  *	domain The domain to allocate from or UMA_ANYDOMAIN.
4404  *	flags  M_WAITOK, M_NOWAIT, M_ZERO.
4405  *
4406  * Returns
4407  *	NULL if there is no memory and M_NOWAIT is set
4408  *	An item if successful
4409  */
4410 
4411 static void *
4412 zone_alloc_item(uma_zone_t zone, void *udata, int domain, int flags)
4413 {
4414 	void *item;
4415 
4416 	if (zone->uz_max_items > 0 && zone_alloc_limit(zone, 1, flags) == 0) {
4417 		counter_u64_add(zone->uz_fails, 1);
4418 		return (NULL);
4419 	}
4420 
4421 	/* Avoid allocs targeting empty domains. */
4422 	if (domain != UMA_ANYDOMAIN && VM_DOMAIN_EMPTY(domain))
4423 		domain = UMA_ANYDOMAIN;
4424 
4425 	if (zone->uz_import(zone->uz_arg, &item, 1, domain, flags) != 1)
4426 		goto fail_cnt;
4427 
4428 	/*
4429 	 * We have to call both the zone's init (not the keg's init)
4430 	 * and the zone's ctor.  This is because the item is going from
4431 	 * a keg slab directly to the user, and the user is expecting it
4432 	 * to be both zone-init'd as well as zone-ctor'd.
4433 	 */
4434 	if (zone->uz_init != NULL) {
4435 		int error;
4436 
4437 		kasan_mark_item_valid(zone, item);
4438 		error = zone->uz_init(item, zone->uz_size, flags);
4439 		kasan_mark_item_invalid(zone, item);
4440 		if (error != 0) {
4441 			zone_free_item(zone, item, udata, SKIP_FINI | SKIP_CNT);
4442 			goto fail_cnt;
4443 		}
4444 	}
4445 	item = item_ctor(zone, zone->uz_flags, zone->uz_size, udata, flags,
4446 	    item);
4447 	if (item == NULL)
4448 		goto fail;
4449 
4450 	counter_u64_add(zone->uz_allocs, 1);
4451 	CTR3(KTR_UMA, "zone_alloc_item item %p from %s(%p)", item,
4452 	    zone->uz_name, zone);
4453 
4454 	return (item);
4455 
4456 fail_cnt:
4457 	counter_u64_add(zone->uz_fails, 1);
4458 fail:
4459 	if (zone->uz_max_items > 0)
4460 		zone_free_limit(zone, 1);
4461 	CTR2(KTR_UMA, "zone_alloc_item failed from %s(%p)",
4462 	    zone->uz_name, zone);
4463 
4464 	return (NULL);
4465 }
4466 
4467 /* See uma.h */
4468 void
4469 uma_zfree_smr(uma_zone_t zone, void *item)
4470 {
4471 	uma_cache_t cache;
4472 	uma_cache_bucket_t bucket;
4473 	int itemdomain;
4474 #ifdef NUMA
4475 	int uz_flags;
4476 #endif
4477 
4478 	CTR3(KTR_UMA, "uma_zfree_smr zone %s(%p) item %p",
4479 	    zone->uz_name, zone, item);
4480 
4481 #ifdef UMA_ZALLOC_DEBUG
4482 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) != 0,
4483 	    ("uma_zfree_smr: called with non-SMR zone."));
4484 	KASSERT(item != NULL, ("uma_zfree_smr: Called with NULL pointer."));
4485 	SMR_ASSERT_NOT_ENTERED(zone->uz_smr);
4486 	if (uma_zfree_debug(zone, item, NULL) == EJUSTRETURN)
4487 		return;
4488 #endif
4489 	cache = &zone->uz_cpu[curcpu];
4490 	itemdomain = 0;
4491 #ifdef NUMA
4492 	uz_flags = cache_uz_flags(cache);
4493 	if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0)
4494 		itemdomain = item_domain(item);
4495 #endif
4496 	critical_enter();
4497 	do {
4498 		cache = &zone->uz_cpu[curcpu];
4499 		/* SMR Zones must free to the free bucket. */
4500 		bucket = &cache->uc_freebucket;
4501 #ifdef NUMA
4502 		if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 &&
4503 		    PCPU_GET(domain) != itemdomain) {
4504 			bucket = &cache->uc_crossbucket;
4505 		}
4506 #endif
4507 		if (__predict_true(bucket->ucb_cnt < bucket->ucb_entries)) {
4508 			cache_bucket_push(cache, bucket, item);
4509 			critical_exit();
4510 			return;
4511 		}
4512 	} while (cache_free(zone, cache, NULL, itemdomain));
4513 	critical_exit();
4514 
4515 	/*
4516 	 * If nothing else caught this, we'll just do an internal free.
4517 	 */
4518 	zone_free_item(zone, item, NULL, SKIP_NONE);
4519 }
4520 
4521 /* See uma.h */
4522 void
4523 uma_zfree_arg(uma_zone_t zone, void *item, void *udata)
4524 {
4525 	uma_cache_t cache;
4526 	uma_cache_bucket_t bucket;
4527 	int itemdomain, uz_flags;
4528 
4529 	/* Enable entropy collection for RANDOM_ENABLE_UMA kernel option */
4530 	random_harvest_fast_uma(&zone, sizeof(zone), RANDOM_UMA);
4531 
4532 	CTR3(KTR_UMA, "uma_zfree_arg zone %s(%p) item %p",
4533 	    zone->uz_name, zone, item);
4534 
4535 #ifdef UMA_ZALLOC_DEBUG
4536 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
4537 	    ("uma_zfree_arg: called with SMR zone."));
4538 	if (uma_zfree_debug(zone, item, udata) == EJUSTRETURN)
4539 		return;
4540 #endif
4541         /* uma_zfree(..., NULL) does nothing, to match free(9). */
4542         if (item == NULL)
4543                 return;
4544 
4545 	/*
4546 	 * We are accessing the per-cpu cache without a critical section to
4547 	 * fetch size and flags.  This is acceptable, if we are preempted we
4548 	 * will simply read another cpu's line.
4549 	 */
4550 	cache = &zone->uz_cpu[curcpu];
4551 	uz_flags = cache_uz_flags(cache);
4552 	if (UMA_ALWAYS_CTORDTOR ||
4553 	    __predict_false((uz_flags & UMA_ZFLAG_CTORDTOR) != 0))
4554 		item_dtor(zone, item, cache_uz_size(cache), udata, SKIP_NONE);
4555 
4556 	/*
4557 	 * The race here is acceptable.  If we miss it we'll just have to wait
4558 	 * a little longer for the limits to be reset.
4559 	 */
4560 	if (__predict_false(uz_flags & UMA_ZFLAG_LIMIT)) {
4561 		if (atomic_load_32(&zone->uz_sleepers) > 0)
4562 			goto zfree_item;
4563 	}
4564 
4565 	/*
4566 	 * If possible, free to the per-CPU cache.  There are two
4567 	 * requirements for safe access to the per-CPU cache: (1) the thread
4568 	 * accessing the cache must not be preempted or yield during access,
4569 	 * and (2) the thread must not migrate CPUs without switching which
4570 	 * cache it accesses.  We rely on a critical section to prevent
4571 	 * preemption and migration.  We release the critical section in
4572 	 * order to acquire the zone mutex if we are unable to free to the
4573 	 * current cache; when we re-acquire the critical section, we must
4574 	 * detect and handle migration if it has occurred.
4575 	 */
4576 	itemdomain = 0;
4577 #ifdef NUMA
4578 	if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0)
4579 		itemdomain = item_domain(item);
4580 #endif
4581 	critical_enter();
4582 	do {
4583 		cache = &zone->uz_cpu[curcpu];
4584 		/*
4585 		 * Try to free into the allocbucket first to give LIFO
4586 		 * ordering for cache-hot datastructures.  Spill over
4587 		 * into the freebucket if necessary.  Alloc will swap
4588 		 * them if one runs dry.
4589 		 */
4590 		bucket = &cache->uc_allocbucket;
4591 #ifdef NUMA
4592 		if ((uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 &&
4593 		    PCPU_GET(domain) != itemdomain) {
4594 			bucket = &cache->uc_crossbucket;
4595 		} else
4596 #endif
4597 		if (bucket->ucb_cnt == bucket->ucb_entries &&
4598 		   cache->uc_freebucket.ucb_cnt <
4599 		   cache->uc_freebucket.ucb_entries)
4600 			cache_bucket_swap(&cache->uc_freebucket,
4601 			    &cache->uc_allocbucket);
4602 		if (__predict_true(bucket->ucb_cnt < bucket->ucb_entries)) {
4603 			cache_bucket_push(cache, bucket, item);
4604 			critical_exit();
4605 			return;
4606 		}
4607 	} while (cache_free(zone, cache, udata, itemdomain));
4608 	critical_exit();
4609 
4610 	/*
4611 	 * If nothing else caught this, we'll just do an internal free.
4612 	 */
4613 zfree_item:
4614 	zone_free_item(zone, item, udata, SKIP_DTOR);
4615 }
4616 
4617 #ifdef NUMA
4618 /*
4619  * sort crossdomain free buckets to domain correct buckets and cache
4620  * them.
4621  */
4622 static void
4623 zone_free_cross(uma_zone_t zone, uma_bucket_t bucket, void *udata)
4624 {
4625 	struct uma_bucketlist emptybuckets, fullbuckets;
4626 	uma_zone_domain_t zdom;
4627 	uma_bucket_t b;
4628 	smr_seq_t seq;
4629 	void *item;
4630 	int domain;
4631 
4632 	CTR3(KTR_UMA,
4633 	    "uma_zfree: zone %s(%p) draining cross bucket %p",
4634 	    zone->uz_name, zone, bucket);
4635 
4636 	/*
4637 	 * It is possible for buckets to arrive here out of order so we fetch
4638 	 * the current smr seq rather than accepting the bucket's.
4639 	 */
4640 	seq = SMR_SEQ_INVALID;
4641 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0)
4642 		seq = smr_advance(zone->uz_smr);
4643 
4644 	/*
4645 	 * To avoid having ndomain * ndomain buckets for sorting we have a
4646 	 * lock on the current crossfree bucket.  A full matrix with
4647 	 * per-domain locking could be used if necessary.
4648 	 */
4649 	STAILQ_INIT(&emptybuckets);
4650 	STAILQ_INIT(&fullbuckets);
4651 	ZONE_CROSS_LOCK(zone);
4652 	for (; bucket->ub_cnt > 0; bucket->ub_cnt--) {
4653 		item = bucket->ub_bucket[bucket->ub_cnt - 1];
4654 		domain = item_domain(item);
4655 		zdom = ZDOM_GET(zone, domain);
4656 		if (zdom->uzd_cross == NULL) {
4657 			if ((b = STAILQ_FIRST(&emptybuckets)) != NULL) {
4658 				STAILQ_REMOVE_HEAD(&emptybuckets, ub_link);
4659 				zdom->uzd_cross = b;
4660 			} else {
4661 				/*
4662 				 * Avoid allocating a bucket with the cross lock
4663 				 * held, since allocation can trigger a
4664 				 * cross-domain free and bucket zones may
4665 				 * allocate from each other.
4666 				 */
4667 				ZONE_CROSS_UNLOCK(zone);
4668 				b = bucket_alloc(zone, udata, M_NOWAIT);
4669 				if (b == NULL)
4670 					goto out;
4671 				ZONE_CROSS_LOCK(zone);
4672 				if (zdom->uzd_cross != NULL) {
4673 					STAILQ_INSERT_HEAD(&emptybuckets, b,
4674 					    ub_link);
4675 				} else {
4676 					zdom->uzd_cross = b;
4677 				}
4678 			}
4679 		}
4680 		b = zdom->uzd_cross;
4681 		b->ub_bucket[b->ub_cnt++] = item;
4682 		b->ub_seq = seq;
4683 		if (b->ub_cnt == b->ub_entries) {
4684 			STAILQ_INSERT_HEAD(&fullbuckets, b, ub_link);
4685 			if ((b = STAILQ_FIRST(&emptybuckets)) != NULL)
4686 				STAILQ_REMOVE_HEAD(&emptybuckets, ub_link);
4687 			zdom->uzd_cross = b;
4688 		}
4689 	}
4690 	ZONE_CROSS_UNLOCK(zone);
4691 out:
4692 	if (bucket->ub_cnt == 0)
4693 		bucket->ub_seq = SMR_SEQ_INVALID;
4694 	bucket_free(zone, bucket, udata);
4695 
4696 	while ((b = STAILQ_FIRST(&emptybuckets)) != NULL) {
4697 		STAILQ_REMOVE_HEAD(&emptybuckets, ub_link);
4698 		bucket_free(zone, b, udata);
4699 	}
4700 	while ((b = STAILQ_FIRST(&fullbuckets)) != NULL) {
4701 		STAILQ_REMOVE_HEAD(&fullbuckets, ub_link);
4702 		domain = item_domain(b->ub_bucket[0]);
4703 		zone_put_bucket(zone, domain, b, udata, true);
4704 	}
4705 }
4706 #endif
4707 
4708 static void
4709 zone_free_bucket(uma_zone_t zone, uma_bucket_t bucket, void *udata,
4710     int itemdomain, bool ws)
4711 {
4712 
4713 #ifdef NUMA
4714 	/*
4715 	 * Buckets coming from the wrong domain will be entirely for the
4716 	 * only other domain on two domain systems.  In this case we can
4717 	 * simply cache them.  Otherwise we need to sort them back to
4718 	 * correct domains.
4719 	 */
4720 	if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 &&
4721 	    vm_ndomains > 2 && PCPU_GET(domain) != itemdomain) {
4722 		zone_free_cross(zone, bucket, udata);
4723 		return;
4724 	}
4725 #endif
4726 
4727 	/*
4728 	 * Attempt to save the bucket in the zone's domain bucket cache.
4729 	 */
4730 	CTR3(KTR_UMA,
4731 	    "uma_zfree: zone %s(%p) putting bucket %p on free list",
4732 	    zone->uz_name, zone, bucket);
4733 	/* ub_cnt is pointing to the last free item */
4734 	if ((zone->uz_flags & UMA_ZONE_ROUNDROBIN) != 0)
4735 		itemdomain = zone_domain_lowest(zone, itemdomain);
4736 	zone_put_bucket(zone, itemdomain, bucket, udata, ws);
4737 }
4738 
4739 /*
4740  * Populate a free or cross bucket for the current cpu cache.  Free any
4741  * existing full bucket either to the zone cache or back to the slab layer.
4742  *
4743  * Enters and returns in a critical section.  false return indicates that
4744  * we can not satisfy this free in the cache layer.  true indicates that
4745  * the caller should retry.
4746  */
4747 static __noinline bool
4748 cache_free(uma_zone_t zone, uma_cache_t cache, void *udata, int itemdomain)
4749 {
4750 	uma_cache_bucket_t cbucket;
4751 	uma_bucket_t newbucket, bucket;
4752 
4753 	CRITICAL_ASSERT(curthread);
4754 
4755 	if (zone->uz_bucket_size == 0)
4756 		return false;
4757 
4758 	cache = &zone->uz_cpu[curcpu];
4759 	newbucket = NULL;
4760 
4761 	/*
4762 	 * FIRSTTOUCH domains need to free to the correct zdom.  When
4763 	 * enabled this is the zdom of the item.   The bucket is the
4764 	 * cross bucket if the current domain and itemdomain do not match.
4765 	 */
4766 	cbucket = &cache->uc_freebucket;
4767 #ifdef NUMA
4768 	if ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) != 0) {
4769 		if (PCPU_GET(domain) != itemdomain) {
4770 			cbucket = &cache->uc_crossbucket;
4771 			if (cbucket->ucb_cnt != 0)
4772 				counter_u64_add(zone->uz_xdomain,
4773 				    cbucket->ucb_cnt);
4774 		}
4775 	}
4776 #endif
4777 	bucket = cache_bucket_unload(cbucket);
4778 	KASSERT(bucket == NULL || bucket->ub_cnt == bucket->ub_entries,
4779 	    ("cache_free: Entered with non-full free bucket."));
4780 
4781 	/* We are no longer associated with this CPU. */
4782 	critical_exit();
4783 
4784 	/*
4785 	 * Don't let SMR zones operate without a free bucket.  Force
4786 	 * a synchronize and re-use this one.  We will only degrade
4787 	 * to a synchronize every bucket_size items rather than every
4788 	 * item if we fail to allocate a bucket.
4789 	 */
4790 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0) {
4791 		if (bucket != NULL)
4792 			bucket->ub_seq = smr_advance(zone->uz_smr);
4793 		newbucket = bucket_alloc(zone, udata, M_NOWAIT);
4794 		if (newbucket == NULL && bucket != NULL) {
4795 			bucket_drain(zone, bucket);
4796 			newbucket = bucket;
4797 			bucket = NULL;
4798 		}
4799 	} else if (!bucketdisable)
4800 		newbucket = bucket_alloc(zone, udata, M_NOWAIT);
4801 
4802 	if (bucket != NULL)
4803 		zone_free_bucket(zone, bucket, udata, itemdomain, true);
4804 
4805 	critical_enter();
4806 	if ((bucket = newbucket) == NULL)
4807 		return (false);
4808 	cache = &zone->uz_cpu[curcpu];
4809 #ifdef NUMA
4810 	/*
4811 	 * Check to see if we should be populating the cross bucket.  If it
4812 	 * is already populated we will fall through and attempt to populate
4813 	 * the free bucket.
4814 	 */
4815 	if ((cache_uz_flags(cache) & UMA_ZONE_FIRSTTOUCH) != 0) {
4816 		if (PCPU_GET(domain) != itemdomain &&
4817 		    cache->uc_crossbucket.ucb_bucket == NULL) {
4818 			cache_bucket_load_cross(cache, bucket);
4819 			return (true);
4820 		}
4821 	}
4822 #endif
4823 	/*
4824 	 * We may have lost the race to fill the bucket or switched CPUs.
4825 	 */
4826 	if (cache->uc_freebucket.ucb_bucket != NULL) {
4827 		critical_exit();
4828 		bucket_free(zone, bucket, udata);
4829 		critical_enter();
4830 	} else
4831 		cache_bucket_load_free(cache, bucket);
4832 
4833 	return (true);
4834 }
4835 
4836 static void
4837 slab_free_item(uma_zone_t zone, uma_slab_t slab, void *item)
4838 {
4839 	uma_keg_t keg;
4840 	uma_domain_t dom;
4841 	int freei;
4842 
4843 	keg = zone->uz_keg;
4844 	KEG_LOCK_ASSERT(keg, slab->us_domain);
4845 
4846 	/* Do we need to remove from any lists? */
4847 	dom = &keg->uk_domain[slab->us_domain];
4848 	if (slab->us_freecount + 1 == keg->uk_ipers) {
4849 		LIST_REMOVE(slab, us_link);
4850 		LIST_INSERT_HEAD(&dom->ud_free_slab, slab, us_link);
4851 		dom->ud_free_slabs++;
4852 	} else if (slab->us_freecount == 0) {
4853 		LIST_REMOVE(slab, us_link);
4854 		LIST_INSERT_HEAD(&dom->ud_part_slab, slab, us_link);
4855 	}
4856 
4857 	/* Slab management. */
4858 	freei = slab_item_index(slab, keg, item);
4859 	BIT_SET(keg->uk_ipers, freei, &slab->us_free);
4860 	slab->us_freecount++;
4861 
4862 	/* Keg statistics. */
4863 	dom->ud_free_items++;
4864 }
4865 
4866 static void
4867 zone_release(void *arg, void **bucket, int cnt)
4868 {
4869 	struct mtx *lock;
4870 	uma_zone_t zone;
4871 	uma_slab_t slab;
4872 	uma_keg_t keg;
4873 	uint8_t *mem;
4874 	void *item;
4875 	int i;
4876 
4877 	zone = arg;
4878 	keg = zone->uz_keg;
4879 	lock = NULL;
4880 	if (__predict_false((zone->uz_flags & UMA_ZFLAG_HASH) != 0))
4881 		lock = KEG_LOCK(keg, 0);
4882 	for (i = 0; i < cnt; i++) {
4883 		item = bucket[i];
4884 		if (__predict_true((zone->uz_flags & UMA_ZFLAG_VTOSLAB) != 0)) {
4885 			slab = vtoslab((vm_offset_t)item);
4886 		} else {
4887 			mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
4888 			if ((zone->uz_flags & UMA_ZFLAG_HASH) != 0)
4889 				slab = hash_sfind(&keg->uk_hash, mem);
4890 			else
4891 				slab = (uma_slab_t)(mem + keg->uk_pgoff);
4892 		}
4893 		if (lock != KEG_LOCKPTR(keg, slab->us_domain)) {
4894 			if (lock != NULL)
4895 				mtx_unlock(lock);
4896 			lock = KEG_LOCK(keg, slab->us_domain);
4897 		}
4898 		slab_free_item(zone, slab, item);
4899 	}
4900 	if (lock != NULL)
4901 		mtx_unlock(lock);
4902 }
4903 
4904 /*
4905  * Frees a single item to any zone.
4906  *
4907  * Arguments:
4908  *	zone   The zone to free to
4909  *	item   The item we're freeing
4910  *	udata  User supplied data for the dtor
4911  *	skip   Skip dtors and finis
4912  */
4913 static __noinline void
4914 zone_free_item(uma_zone_t zone, void *item, void *udata, enum zfreeskip skip)
4915 {
4916 
4917 	/*
4918 	 * If a free is sent directly to an SMR zone we have to
4919 	 * synchronize immediately because the item can instantly
4920 	 * be reallocated. This should only happen in degenerate
4921 	 * cases when no memory is available for per-cpu caches.
4922 	 */
4923 	if ((zone->uz_flags & UMA_ZONE_SMR) != 0 && skip == SKIP_NONE)
4924 		smr_synchronize(zone->uz_smr);
4925 
4926 	item_dtor(zone, item, zone->uz_size, udata, skip);
4927 
4928 	if (skip < SKIP_FINI && zone->uz_fini) {
4929 		kasan_mark_item_valid(zone, item);
4930 		zone->uz_fini(item, zone->uz_size);
4931 		kasan_mark_item_invalid(zone, item);
4932 	}
4933 
4934 	zone->uz_release(zone->uz_arg, &item, 1);
4935 
4936 	if (skip & SKIP_CNT)
4937 		return;
4938 
4939 	counter_u64_add(zone->uz_frees, 1);
4940 
4941 	if (zone->uz_max_items > 0)
4942 		zone_free_limit(zone, 1);
4943 }
4944 
4945 /* See uma.h */
4946 int
4947 uma_zone_set_max(uma_zone_t zone, int nitems)
4948 {
4949 
4950 	/*
4951 	 * If the limit is small, we may need to constrain the maximum per-CPU
4952 	 * cache size, or disable caching entirely.
4953 	 */
4954 	uma_zone_set_maxcache(zone, nitems);
4955 
4956 	/*
4957 	 * XXX This can misbehave if the zone has any allocations with
4958 	 * no limit and a limit is imposed.  There is currently no
4959 	 * way to clear a limit.
4960 	 */
4961 	ZONE_LOCK(zone);
4962 	if (zone->uz_max_items == 0)
4963 		ZONE_ASSERT_COLD(zone);
4964 	zone->uz_max_items = nitems;
4965 	zone->uz_flags |= UMA_ZFLAG_LIMIT;
4966 	zone_update_caches(zone);
4967 	/* We may need to wake waiters. */
4968 	wakeup(&zone->uz_max_items);
4969 	ZONE_UNLOCK(zone);
4970 
4971 	return (nitems);
4972 }
4973 
4974 /* See uma.h */
4975 void
4976 uma_zone_set_maxcache(uma_zone_t zone, int nitems)
4977 {
4978 	int bpcpu, bpdom, bsize, nb;
4979 
4980 	ZONE_LOCK(zone);
4981 
4982 	/*
4983 	 * Compute a lower bound on the number of items that may be cached in
4984 	 * the zone.  Each CPU gets at least two buckets, and for cross-domain
4985 	 * frees we use an additional bucket per CPU and per domain.  Select the
4986 	 * largest bucket size that does not exceed half of the requested limit,
4987 	 * with the left over space given to the full bucket cache.
4988 	 */
4989 	bpdom = 0;
4990 	bpcpu = 2;
4991 #ifdef NUMA
4992 	if ((zone->uz_flags & UMA_ZONE_FIRSTTOUCH) != 0 && vm_ndomains > 1) {
4993 		bpcpu++;
4994 		bpdom++;
4995 	}
4996 #endif
4997 	nb = bpcpu * mp_ncpus + bpdom * vm_ndomains;
4998 	bsize = nitems / nb / 2;
4999 	if (bsize > BUCKET_MAX)
5000 		bsize = BUCKET_MAX;
5001 	else if (bsize == 0 && nitems / nb > 0)
5002 		bsize = 1;
5003 	zone->uz_bucket_size_max = zone->uz_bucket_size = bsize;
5004 	if (zone->uz_bucket_size_min > zone->uz_bucket_size_max)
5005 		zone->uz_bucket_size_min = zone->uz_bucket_size_max;
5006 	zone->uz_bucket_max = nitems - nb * bsize;
5007 	ZONE_UNLOCK(zone);
5008 }
5009 
5010 /* See uma.h */
5011 int
5012 uma_zone_get_max(uma_zone_t zone)
5013 {
5014 	int nitems;
5015 
5016 	nitems = atomic_load_64(&zone->uz_max_items);
5017 
5018 	return (nitems);
5019 }
5020 
5021 /* See uma.h */
5022 void
5023 uma_zone_set_warning(uma_zone_t zone, const char *warning)
5024 {
5025 
5026 	ZONE_ASSERT_COLD(zone);
5027 	zone->uz_warning = warning;
5028 }
5029 
5030 /* See uma.h */
5031 void
5032 uma_zone_set_maxaction(uma_zone_t zone, uma_maxaction_t maxaction)
5033 {
5034 
5035 	ZONE_ASSERT_COLD(zone);
5036 	TASK_INIT(&zone->uz_maxaction, 0, (task_fn_t *)maxaction, zone);
5037 }
5038 
5039 /* See uma.h */
5040 int
5041 uma_zone_get_cur(uma_zone_t zone)
5042 {
5043 	int64_t nitems;
5044 	u_int i;
5045 
5046 	nitems = 0;
5047 	if (zone->uz_allocs != EARLY_COUNTER && zone->uz_frees != EARLY_COUNTER)
5048 		nitems = counter_u64_fetch(zone->uz_allocs) -
5049 		    counter_u64_fetch(zone->uz_frees);
5050 	CPU_FOREACH(i)
5051 		nitems += atomic_load_64(&zone->uz_cpu[i].uc_allocs) -
5052 		    atomic_load_64(&zone->uz_cpu[i].uc_frees);
5053 
5054 	return (nitems < 0 ? 0 : nitems);
5055 }
5056 
5057 static uint64_t
5058 uma_zone_get_allocs(uma_zone_t zone)
5059 {
5060 	uint64_t nitems;
5061 	u_int i;
5062 
5063 	nitems = 0;
5064 	if (zone->uz_allocs != EARLY_COUNTER)
5065 		nitems = counter_u64_fetch(zone->uz_allocs);
5066 	CPU_FOREACH(i)
5067 		nitems += atomic_load_64(&zone->uz_cpu[i].uc_allocs);
5068 
5069 	return (nitems);
5070 }
5071 
5072 static uint64_t
5073 uma_zone_get_frees(uma_zone_t zone)
5074 {
5075 	uint64_t nitems;
5076 	u_int i;
5077 
5078 	nitems = 0;
5079 	if (zone->uz_frees != EARLY_COUNTER)
5080 		nitems = counter_u64_fetch(zone->uz_frees);
5081 	CPU_FOREACH(i)
5082 		nitems += atomic_load_64(&zone->uz_cpu[i].uc_frees);
5083 
5084 	return (nitems);
5085 }
5086 
5087 #ifdef INVARIANTS
5088 /* Used only for KEG_ASSERT_COLD(). */
5089 static uint64_t
5090 uma_keg_get_allocs(uma_keg_t keg)
5091 {
5092 	uma_zone_t z;
5093 	uint64_t nitems;
5094 
5095 	nitems = 0;
5096 	LIST_FOREACH(z, &keg->uk_zones, uz_link)
5097 		nitems += uma_zone_get_allocs(z);
5098 
5099 	return (nitems);
5100 }
5101 #endif
5102 
5103 /* See uma.h */
5104 void
5105 uma_zone_set_init(uma_zone_t zone, uma_init uminit)
5106 {
5107 	uma_keg_t keg;
5108 
5109 	KEG_GET(zone, keg);
5110 	KEG_ASSERT_COLD(keg);
5111 	keg->uk_init = uminit;
5112 }
5113 
5114 /* See uma.h */
5115 void
5116 uma_zone_set_fini(uma_zone_t zone, uma_fini fini)
5117 {
5118 	uma_keg_t keg;
5119 
5120 	KEG_GET(zone, keg);
5121 	KEG_ASSERT_COLD(keg);
5122 	keg->uk_fini = fini;
5123 }
5124 
5125 /* See uma.h */
5126 void
5127 uma_zone_set_zinit(uma_zone_t zone, uma_init zinit)
5128 {
5129 
5130 	ZONE_ASSERT_COLD(zone);
5131 	zone->uz_init = zinit;
5132 }
5133 
5134 /* See uma.h */
5135 void
5136 uma_zone_set_zfini(uma_zone_t zone, uma_fini zfini)
5137 {
5138 
5139 	ZONE_ASSERT_COLD(zone);
5140 	zone->uz_fini = zfini;
5141 }
5142 
5143 /* See uma.h */
5144 void
5145 uma_zone_set_freef(uma_zone_t zone, uma_free freef)
5146 {
5147 	uma_keg_t keg;
5148 
5149 	KEG_GET(zone, keg);
5150 	KEG_ASSERT_COLD(keg);
5151 	keg->uk_freef = freef;
5152 }
5153 
5154 /* See uma.h */
5155 void
5156 uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf)
5157 {
5158 	uma_keg_t keg;
5159 
5160 	KEG_GET(zone, keg);
5161 	KEG_ASSERT_COLD(keg);
5162 	keg->uk_allocf = allocf;
5163 }
5164 
5165 /* See uma.h */
5166 void
5167 uma_zone_set_smr(uma_zone_t zone, smr_t smr)
5168 {
5169 
5170 	ZONE_ASSERT_COLD(zone);
5171 
5172 	KASSERT(smr != NULL, ("Got NULL smr"));
5173 	KASSERT((zone->uz_flags & UMA_ZONE_SMR) == 0,
5174 	    ("zone %p (%s) already uses SMR", zone, zone->uz_name));
5175 	zone->uz_flags |= UMA_ZONE_SMR;
5176 	zone->uz_smr = smr;
5177 	zone_update_caches(zone);
5178 }
5179 
5180 smr_t
5181 uma_zone_get_smr(uma_zone_t zone)
5182 {
5183 
5184 	return (zone->uz_smr);
5185 }
5186 
5187 /* See uma.h */
5188 void
5189 uma_zone_reserve(uma_zone_t zone, int items)
5190 {
5191 	uma_keg_t keg;
5192 
5193 	KEG_GET(zone, keg);
5194 	KEG_ASSERT_COLD(keg);
5195 	keg->uk_reserve = items;
5196 }
5197 
5198 /* See uma.h */
5199 int
5200 uma_zone_reserve_kva(uma_zone_t zone, int count)
5201 {
5202 	uma_keg_t keg;
5203 	vm_offset_t kva;
5204 	u_int pages;
5205 
5206 	KEG_GET(zone, keg);
5207 	KEG_ASSERT_COLD(keg);
5208 	ZONE_ASSERT_COLD(zone);
5209 
5210 	pages = howmany(count, keg->uk_ipers) * keg->uk_ppera;
5211 
5212 #ifdef UMA_USE_DMAP
5213 	if (keg->uk_ppera > 1) {
5214 #else
5215 	if (1) {
5216 #endif
5217 		kva = kva_alloc((vm_size_t)pages * PAGE_SIZE);
5218 		if (kva == 0)
5219 			return (0);
5220 	} else
5221 		kva = 0;
5222 
5223 	MPASS(keg->uk_kva == 0);
5224 	keg->uk_kva = kva;
5225 	keg->uk_offset = 0;
5226 	zone->uz_max_items = pages * keg->uk_ipers;
5227 #ifdef UMA_USE_DMAP
5228 	keg->uk_allocf = (keg->uk_ppera > 1) ? noobj_alloc : uma_small_alloc;
5229 #else
5230 	keg->uk_allocf = noobj_alloc;
5231 #endif
5232 	keg->uk_flags |= UMA_ZFLAG_LIMIT | UMA_ZONE_NOFREE;
5233 	zone->uz_flags |= UMA_ZFLAG_LIMIT | UMA_ZONE_NOFREE;
5234 	zone_update_caches(zone);
5235 
5236 	return (1);
5237 }
5238 
5239 /* See uma.h */
5240 void
5241 uma_prealloc(uma_zone_t zone, int items)
5242 {
5243 	struct vm_domainset_iter di;
5244 	uma_domain_t dom;
5245 	uma_slab_t slab;
5246 	uma_keg_t keg;
5247 	int aflags, domain, slabs;
5248 
5249 	KEG_GET(zone, keg);
5250 	slabs = howmany(items, keg->uk_ipers);
5251 	while (slabs-- > 0) {
5252 		aflags = M_NOWAIT;
5253 		vm_domainset_iter_policy_ref_init(&di, &keg->uk_dr, &domain,
5254 		    &aflags);
5255 		for (;;) {
5256 			slab = keg_alloc_slab(keg, zone, domain, M_WAITOK,
5257 			    aflags);
5258 			if (slab != NULL) {
5259 				dom = &keg->uk_domain[slab->us_domain];
5260 				/*
5261 				 * keg_alloc_slab() always returns a slab on the
5262 				 * partial list.
5263 				 */
5264 				LIST_REMOVE(slab, us_link);
5265 				LIST_INSERT_HEAD(&dom->ud_free_slab, slab,
5266 				    us_link);
5267 				dom->ud_free_slabs++;
5268 				KEG_UNLOCK(keg, slab->us_domain);
5269 				break;
5270 			}
5271 			if (vm_domainset_iter_policy(&di, &domain) != 0)
5272 				vm_wait_doms(&keg->uk_dr.dr_policy->ds_mask, 0);
5273 		}
5274 	}
5275 }
5276 
5277 /*
5278  * Returns a snapshot of memory consumption in bytes.
5279  */
5280 size_t
5281 uma_zone_memory(uma_zone_t zone)
5282 {
5283 	size_t sz;
5284 	int i;
5285 
5286 	sz = 0;
5287 	if (zone->uz_flags & UMA_ZFLAG_CACHE) {
5288 		for (i = 0; i < vm_ndomains; i++)
5289 			sz += ZDOM_GET(zone, i)->uzd_nitems;
5290 		return (sz * zone->uz_size);
5291 	}
5292 	for (i = 0; i < vm_ndomains; i++)
5293 		sz += zone->uz_keg->uk_domain[i].ud_pages;
5294 
5295 	return (sz * PAGE_SIZE);
5296 }
5297 
5298 struct uma_reclaim_args {
5299 	int	domain;
5300 	int	req;
5301 };
5302 
5303 static void
5304 uma_reclaim_domain_cb(uma_zone_t zone, void *arg)
5305 {
5306 	struct uma_reclaim_args *args;
5307 
5308 	args = arg;
5309 	if ((zone->uz_flags & UMA_ZONE_UNMANAGED) == 0)
5310 		uma_zone_reclaim_domain(zone, args->req, args->domain);
5311 }
5312 
5313 /* See uma.h */
5314 void
5315 uma_reclaim(int req)
5316 {
5317 	uma_reclaim_domain(req, UMA_ANYDOMAIN);
5318 }
5319 
5320 void
5321 uma_reclaim_domain(int req, int domain)
5322 {
5323 	struct uma_reclaim_args args;
5324 
5325 	bucket_enable();
5326 
5327 	args.domain = domain;
5328 	args.req = req;
5329 
5330 	sx_slock(&uma_reclaim_lock);
5331 	switch (req) {
5332 	case UMA_RECLAIM_TRIM:
5333 	case UMA_RECLAIM_DRAIN:
5334 		zone_foreach(uma_reclaim_domain_cb, &args);
5335 		break;
5336 	case UMA_RECLAIM_DRAIN_CPU:
5337 		zone_foreach(uma_reclaim_domain_cb, &args);
5338 		pcpu_cache_drain_safe(NULL);
5339 		zone_foreach(uma_reclaim_domain_cb, &args);
5340 		break;
5341 	default:
5342 		panic("unhandled reclamation request %d", req);
5343 	}
5344 
5345 	/*
5346 	 * Some slabs may have been freed but this zone will be visited early
5347 	 * we visit again so that we can free pages that are empty once other
5348 	 * zones are drained.  We have to do the same for buckets.
5349 	 */
5350 	uma_zone_reclaim_domain(slabzones[0], UMA_RECLAIM_DRAIN, domain);
5351 	uma_zone_reclaim_domain(slabzones[1], UMA_RECLAIM_DRAIN, domain);
5352 	bucket_zone_drain(domain);
5353 	sx_sunlock(&uma_reclaim_lock);
5354 }
5355 
5356 static volatile int uma_reclaim_needed;
5357 
5358 void
5359 uma_reclaim_wakeup(void)
5360 {
5361 
5362 	if (atomic_fetchadd_int(&uma_reclaim_needed, 1) == 0)
5363 		wakeup(uma_reclaim);
5364 }
5365 
5366 void
5367 uma_reclaim_worker(void *arg __unused)
5368 {
5369 
5370 	for (;;) {
5371 		sx_xlock(&uma_reclaim_lock);
5372 		while (atomic_load_int(&uma_reclaim_needed) == 0)
5373 			sx_sleep(uma_reclaim, &uma_reclaim_lock, PVM, "umarcl",
5374 			    hz);
5375 		sx_xunlock(&uma_reclaim_lock);
5376 		EVENTHANDLER_INVOKE(vm_lowmem, VM_LOW_KMEM);
5377 		uma_reclaim(UMA_RECLAIM_DRAIN_CPU);
5378 		atomic_store_int(&uma_reclaim_needed, 0);
5379 		/* Don't fire more than once per-second. */
5380 		pause("umarclslp", hz);
5381 	}
5382 }
5383 
5384 /* See uma.h */
5385 void
5386 uma_zone_reclaim(uma_zone_t zone, int req)
5387 {
5388 	uma_zone_reclaim_domain(zone, req, UMA_ANYDOMAIN);
5389 }
5390 
5391 void
5392 uma_zone_reclaim_domain(uma_zone_t zone, int req, int domain)
5393 {
5394 	switch (req) {
5395 	case UMA_RECLAIM_TRIM:
5396 		zone_reclaim(zone, domain, M_NOWAIT, false);
5397 		break;
5398 	case UMA_RECLAIM_DRAIN:
5399 		zone_reclaim(zone, domain, M_NOWAIT, true);
5400 		break;
5401 	case UMA_RECLAIM_DRAIN_CPU:
5402 		pcpu_cache_drain_safe(zone);
5403 		zone_reclaim(zone, domain, M_NOWAIT, true);
5404 		break;
5405 	default:
5406 		panic("unhandled reclamation request %d", req);
5407 	}
5408 }
5409 
5410 /* See uma.h */
5411 int
5412 uma_zone_exhausted(uma_zone_t zone)
5413 {
5414 
5415 	return (atomic_load_32(&zone->uz_sleepers) > 0);
5416 }
5417 
5418 unsigned long
5419 uma_limit(void)
5420 {
5421 
5422 	return (uma_kmem_limit);
5423 }
5424 
5425 void
5426 uma_set_limit(unsigned long limit)
5427 {
5428 
5429 	uma_kmem_limit = limit;
5430 }
5431 
5432 unsigned long
5433 uma_size(void)
5434 {
5435 
5436 	return (atomic_load_long(&uma_kmem_total));
5437 }
5438 
5439 long
5440 uma_avail(void)
5441 {
5442 
5443 	return (uma_kmem_limit - uma_size());
5444 }
5445 
5446 #ifdef DDB
5447 /*
5448  * Generate statistics across both the zone and its per-cpu cache's.  Return
5449  * desired statistics if the pointer is non-NULL for that statistic.
5450  *
5451  * Note: does not update the zone statistics, as it can't safely clear the
5452  * per-CPU cache statistic.
5453  *
5454  */
5455 static void
5456 uma_zone_sumstat(uma_zone_t z, long *cachefreep, uint64_t *allocsp,
5457     uint64_t *freesp, uint64_t *sleepsp, uint64_t *xdomainp)
5458 {
5459 	uma_cache_t cache;
5460 	uint64_t allocs, frees, sleeps, xdomain;
5461 	int cachefree, cpu;
5462 
5463 	allocs = frees = sleeps = xdomain = 0;
5464 	cachefree = 0;
5465 	CPU_FOREACH(cpu) {
5466 		cache = &z->uz_cpu[cpu];
5467 		cachefree += cache->uc_allocbucket.ucb_cnt;
5468 		cachefree += cache->uc_freebucket.ucb_cnt;
5469 		xdomain += cache->uc_crossbucket.ucb_cnt;
5470 		cachefree += cache->uc_crossbucket.ucb_cnt;
5471 		allocs += cache->uc_allocs;
5472 		frees += cache->uc_frees;
5473 	}
5474 	allocs += counter_u64_fetch(z->uz_allocs);
5475 	frees += counter_u64_fetch(z->uz_frees);
5476 	xdomain += counter_u64_fetch(z->uz_xdomain);
5477 	sleeps += z->uz_sleeps;
5478 	if (cachefreep != NULL)
5479 		*cachefreep = cachefree;
5480 	if (allocsp != NULL)
5481 		*allocsp = allocs;
5482 	if (freesp != NULL)
5483 		*freesp = frees;
5484 	if (sleepsp != NULL)
5485 		*sleepsp = sleeps;
5486 	if (xdomainp != NULL)
5487 		*xdomainp = xdomain;
5488 }
5489 #endif /* DDB */
5490 
5491 static int
5492 sysctl_vm_zone_count(SYSCTL_HANDLER_ARGS)
5493 {
5494 	uma_keg_t kz;
5495 	uma_zone_t z;
5496 	int count;
5497 
5498 	count = 0;
5499 	rw_rlock(&uma_rwlock);
5500 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
5501 		LIST_FOREACH(z, &kz->uk_zones, uz_link)
5502 			count++;
5503 	}
5504 	LIST_FOREACH(z, &uma_cachezones, uz_link)
5505 		count++;
5506 
5507 	rw_runlock(&uma_rwlock);
5508 	return (sysctl_handle_int(oidp, &count, 0, req));
5509 }
5510 
5511 static void
5512 uma_vm_zone_stats(struct uma_type_header *uth, uma_zone_t z, struct sbuf *sbuf,
5513     struct uma_percpu_stat *ups, bool internal)
5514 {
5515 	uma_zone_domain_t zdom;
5516 	uma_cache_t cache;
5517 	int i;
5518 
5519 	for (i = 0; i < vm_ndomains; i++) {
5520 		zdom = ZDOM_GET(z, i);
5521 		uth->uth_zone_free += zdom->uzd_nitems;
5522 	}
5523 	uth->uth_allocs = counter_u64_fetch(z->uz_allocs);
5524 	uth->uth_frees = counter_u64_fetch(z->uz_frees);
5525 	uth->uth_fails = counter_u64_fetch(z->uz_fails);
5526 	uth->uth_xdomain = counter_u64_fetch(z->uz_xdomain);
5527 	uth->uth_sleeps = z->uz_sleeps;
5528 
5529 	for (i = 0; i < mp_maxid + 1; i++) {
5530 		bzero(&ups[i], sizeof(*ups));
5531 		if (internal || CPU_ABSENT(i))
5532 			continue;
5533 		cache = &z->uz_cpu[i];
5534 		ups[i].ups_cache_free += cache->uc_allocbucket.ucb_cnt;
5535 		ups[i].ups_cache_free += cache->uc_freebucket.ucb_cnt;
5536 		ups[i].ups_cache_free += cache->uc_crossbucket.ucb_cnt;
5537 		ups[i].ups_allocs = cache->uc_allocs;
5538 		ups[i].ups_frees = cache->uc_frees;
5539 	}
5540 }
5541 
5542 static int
5543 sysctl_vm_zone_stats(SYSCTL_HANDLER_ARGS)
5544 {
5545 	struct uma_stream_header ush;
5546 	struct uma_type_header uth;
5547 	struct uma_percpu_stat *ups;
5548 	struct sbuf sbuf;
5549 	uma_keg_t kz;
5550 	uma_zone_t z;
5551 	uint64_t items;
5552 	uint32_t kfree, pages;
5553 	int count, error, i;
5554 
5555 	error = sysctl_wire_old_buffer(req, 0);
5556 	if (error != 0)
5557 		return (error);
5558 	sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
5559 	sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL);
5560 	ups = malloc((mp_maxid + 1) * sizeof(*ups), M_TEMP, M_WAITOK);
5561 
5562 	count = 0;
5563 	rw_rlock(&uma_rwlock);
5564 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
5565 		LIST_FOREACH(z, &kz->uk_zones, uz_link)
5566 			count++;
5567 	}
5568 
5569 	LIST_FOREACH(z, &uma_cachezones, uz_link)
5570 		count++;
5571 
5572 	/*
5573 	 * Insert stream header.
5574 	 */
5575 	bzero(&ush, sizeof(ush));
5576 	ush.ush_version = UMA_STREAM_VERSION;
5577 	ush.ush_maxcpus = (mp_maxid + 1);
5578 	ush.ush_count = count;
5579 	(void)sbuf_bcat(&sbuf, &ush, sizeof(ush));
5580 
5581 	LIST_FOREACH(kz, &uma_kegs, uk_link) {
5582 		kfree = pages = 0;
5583 		for (i = 0; i < vm_ndomains; i++) {
5584 			kfree += kz->uk_domain[i].ud_free_items;
5585 			pages += kz->uk_domain[i].ud_pages;
5586 		}
5587 		LIST_FOREACH(z, &kz->uk_zones, uz_link) {
5588 			bzero(&uth, sizeof(uth));
5589 			strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
5590 			uth.uth_align = kz->uk_align;
5591 			uth.uth_size = kz->uk_size;
5592 			uth.uth_rsize = kz->uk_rsize;
5593 			if (z->uz_max_items > 0) {
5594 				items = UZ_ITEMS_COUNT(z->uz_items);
5595 				uth.uth_pages = (items / kz->uk_ipers) *
5596 					kz->uk_ppera;
5597 			} else
5598 				uth.uth_pages = pages;
5599 			uth.uth_maxpages = (z->uz_max_items / kz->uk_ipers) *
5600 			    kz->uk_ppera;
5601 			uth.uth_limit = z->uz_max_items;
5602 			uth.uth_keg_free = kfree;
5603 
5604 			/*
5605 			 * A zone is secondary is it is not the first entry
5606 			 * on the keg's zone list.
5607 			 */
5608 			if ((z->uz_flags & UMA_ZONE_SECONDARY) &&
5609 			    (LIST_FIRST(&kz->uk_zones) != z))
5610 				uth.uth_zone_flags = UTH_ZONE_SECONDARY;
5611 			uma_vm_zone_stats(&uth, z, &sbuf, ups,
5612 			    kz->uk_flags & UMA_ZFLAG_INTERNAL);
5613 			(void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
5614 			for (i = 0; i < mp_maxid + 1; i++)
5615 				(void)sbuf_bcat(&sbuf, &ups[i], sizeof(ups[i]));
5616 		}
5617 	}
5618 	LIST_FOREACH(z, &uma_cachezones, uz_link) {
5619 		bzero(&uth, sizeof(uth));
5620 		strlcpy(uth.uth_name, z->uz_name, UTH_MAX_NAME);
5621 		uth.uth_size = z->uz_size;
5622 		uma_vm_zone_stats(&uth, z, &sbuf, ups, false);
5623 		(void)sbuf_bcat(&sbuf, &uth, sizeof(uth));
5624 		for (i = 0; i < mp_maxid + 1; i++)
5625 			(void)sbuf_bcat(&sbuf, &ups[i], sizeof(ups[i]));
5626 	}
5627 
5628 	rw_runlock(&uma_rwlock);
5629 	error = sbuf_finish(&sbuf);
5630 	sbuf_delete(&sbuf);
5631 	free(ups, M_TEMP);
5632 	return (error);
5633 }
5634 
5635 int
5636 sysctl_handle_uma_zone_max(SYSCTL_HANDLER_ARGS)
5637 {
5638 	uma_zone_t zone = *(uma_zone_t *)arg1;
5639 	int error, max;
5640 
5641 	max = uma_zone_get_max(zone);
5642 	error = sysctl_handle_int(oidp, &max, 0, req);
5643 	if (error || !req->newptr)
5644 		return (error);
5645 
5646 	uma_zone_set_max(zone, max);
5647 
5648 	return (0);
5649 }
5650 
5651 int
5652 sysctl_handle_uma_zone_cur(SYSCTL_HANDLER_ARGS)
5653 {
5654 	uma_zone_t zone;
5655 	int cur;
5656 
5657 	/*
5658 	 * Some callers want to add sysctls for global zones that
5659 	 * may not yet exist so they pass a pointer to a pointer.
5660 	 */
5661 	if (arg2 == 0)
5662 		zone = *(uma_zone_t *)arg1;
5663 	else
5664 		zone = arg1;
5665 	cur = uma_zone_get_cur(zone);
5666 	return (sysctl_handle_int(oidp, &cur, 0, req));
5667 }
5668 
5669 static int
5670 sysctl_handle_uma_zone_allocs(SYSCTL_HANDLER_ARGS)
5671 {
5672 	uma_zone_t zone = arg1;
5673 	uint64_t cur;
5674 
5675 	cur = uma_zone_get_allocs(zone);
5676 	return (sysctl_handle_64(oidp, &cur, 0, req));
5677 }
5678 
5679 static int
5680 sysctl_handle_uma_zone_frees(SYSCTL_HANDLER_ARGS)
5681 {
5682 	uma_zone_t zone = arg1;
5683 	uint64_t cur;
5684 
5685 	cur = uma_zone_get_frees(zone);
5686 	return (sysctl_handle_64(oidp, &cur, 0, req));
5687 }
5688 
5689 static int
5690 sysctl_handle_uma_zone_flags(SYSCTL_HANDLER_ARGS)
5691 {
5692 	struct sbuf sbuf;
5693 	uma_zone_t zone = arg1;
5694 	int error;
5695 
5696 	sbuf_new_for_sysctl(&sbuf, NULL, 0, req);
5697 	if (zone->uz_flags != 0)
5698 		sbuf_printf(&sbuf, "0x%b", zone->uz_flags, PRINT_UMA_ZFLAGS);
5699 	else
5700 		sbuf_printf(&sbuf, "0");
5701 	error = sbuf_finish(&sbuf);
5702 	sbuf_delete(&sbuf);
5703 
5704 	return (error);
5705 }
5706 
5707 static int
5708 sysctl_handle_uma_slab_efficiency(SYSCTL_HANDLER_ARGS)
5709 {
5710 	uma_keg_t keg = arg1;
5711 	int avail, effpct, total;
5712 
5713 	total = keg->uk_ppera * PAGE_SIZE;
5714 	if ((keg->uk_flags & UMA_ZFLAG_OFFPAGE) != 0)
5715 		total += slabzone(keg->uk_ipers)->uz_keg->uk_rsize;
5716 	/*
5717 	 * We consider the client's requested size and alignment here, not the
5718 	 * real size determination uk_rsize, because we also adjust the real
5719 	 * size for internal implementation reasons (max bitset size).
5720 	 */
5721 	avail = keg->uk_ipers * roundup2(keg->uk_size, keg->uk_align + 1);
5722 	if ((keg->uk_flags & UMA_ZONE_PCPU) != 0)
5723 		avail *= mp_maxid + 1;
5724 	effpct = 100 * avail / total;
5725 	return (sysctl_handle_int(oidp, &effpct, 0, req));
5726 }
5727 
5728 static int
5729 sysctl_handle_uma_zone_items(SYSCTL_HANDLER_ARGS)
5730 {
5731 	uma_zone_t zone = arg1;
5732 	uint64_t cur;
5733 
5734 	cur = UZ_ITEMS_COUNT(atomic_load_64(&zone->uz_items));
5735 	return (sysctl_handle_64(oidp, &cur, 0, req));
5736 }
5737 
5738 #ifdef INVARIANTS
5739 static uma_slab_t
5740 uma_dbg_getslab(uma_zone_t zone, void *item)
5741 {
5742 	uma_slab_t slab;
5743 	uma_keg_t keg;
5744 	uint8_t *mem;
5745 
5746 	/*
5747 	 * It is safe to return the slab here even though the
5748 	 * zone is unlocked because the item's allocation state
5749 	 * essentially holds a reference.
5750 	 */
5751 	mem = (uint8_t *)((uintptr_t)item & (~UMA_SLAB_MASK));
5752 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
5753 		return (NULL);
5754 	if (zone->uz_flags & UMA_ZFLAG_VTOSLAB)
5755 		return (vtoslab((vm_offset_t)mem));
5756 	keg = zone->uz_keg;
5757 	if ((keg->uk_flags & UMA_ZFLAG_HASH) == 0)
5758 		return ((uma_slab_t)(mem + keg->uk_pgoff));
5759 	KEG_LOCK(keg, 0);
5760 	slab = hash_sfind(&keg->uk_hash, mem);
5761 	KEG_UNLOCK(keg, 0);
5762 
5763 	return (slab);
5764 }
5765 
5766 static bool
5767 uma_dbg_zskip(uma_zone_t zone, void *mem)
5768 {
5769 
5770 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
5771 		return (true);
5772 
5773 	return (uma_dbg_kskip(zone->uz_keg, mem));
5774 }
5775 
5776 static bool
5777 uma_dbg_kskip(uma_keg_t keg, void *mem)
5778 {
5779 	uintptr_t idx;
5780 
5781 	if (dbg_divisor == 0)
5782 		return (true);
5783 
5784 	if (dbg_divisor == 1)
5785 		return (false);
5786 
5787 	idx = (uintptr_t)mem >> PAGE_SHIFT;
5788 	if (keg->uk_ipers > 1) {
5789 		idx *= keg->uk_ipers;
5790 		idx += ((uintptr_t)mem & PAGE_MASK) / keg->uk_rsize;
5791 	}
5792 
5793 	if ((idx / dbg_divisor) * dbg_divisor != idx) {
5794 		counter_u64_add(uma_skip_cnt, 1);
5795 		return (true);
5796 	}
5797 	counter_u64_add(uma_dbg_cnt, 1);
5798 
5799 	return (false);
5800 }
5801 
5802 /*
5803  * Set up the slab's freei data such that uma_dbg_free can function.
5804  *
5805  */
5806 static void
5807 uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item)
5808 {
5809 	uma_keg_t keg;
5810 	int freei;
5811 
5812 	if (slab == NULL) {
5813 		slab = uma_dbg_getslab(zone, item);
5814 		if (slab == NULL)
5815 			panic("uma: item %p did not belong to zone %s",
5816 			    item, zone->uz_name);
5817 	}
5818 	keg = zone->uz_keg;
5819 	freei = slab_item_index(slab, keg, item);
5820 
5821 	if (BIT_TEST_SET_ATOMIC(keg->uk_ipers, freei,
5822 	    slab_dbg_bits(slab, keg)))
5823 		panic("Duplicate alloc of %p from zone %p(%s) slab %p(%d)",
5824 		    item, zone, zone->uz_name, slab, freei);
5825 }
5826 
5827 /*
5828  * Verifies freed addresses.  Checks for alignment, valid slab membership
5829  * and duplicate frees.
5830  *
5831  */
5832 static void
5833 uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item)
5834 {
5835 	uma_keg_t keg;
5836 	int freei;
5837 
5838 	if (slab == NULL) {
5839 		slab = uma_dbg_getslab(zone, item);
5840 		if (slab == NULL)
5841 			panic("uma: Freed item %p did not belong to zone %s",
5842 			    item, zone->uz_name);
5843 	}
5844 	keg = zone->uz_keg;
5845 	freei = slab_item_index(slab, keg, item);
5846 
5847 	if (freei >= keg->uk_ipers)
5848 		panic("Invalid free of %p from zone %p(%s) slab %p(%d)",
5849 		    item, zone, zone->uz_name, slab, freei);
5850 
5851 	if (slab_item(slab, keg, freei) != item)
5852 		panic("Unaligned free of %p from zone %p(%s) slab %p(%d)",
5853 		    item, zone, zone->uz_name, slab, freei);
5854 
5855 	if (!BIT_TEST_CLR_ATOMIC(keg->uk_ipers, freei,
5856 	    slab_dbg_bits(slab, keg)))
5857 		panic("Duplicate free of %p from zone %p(%s) slab %p(%d)",
5858 		    item, zone, zone->uz_name, slab, freei);
5859 }
5860 #endif /* INVARIANTS */
5861 
5862 #ifdef DDB
5863 static int64_t
5864 get_uma_stats(uma_keg_t kz, uma_zone_t z, uint64_t *allocs, uint64_t *used,
5865     uint64_t *sleeps, long *cachefree, uint64_t *xdomain)
5866 {
5867 	uint64_t frees;
5868 	int i;
5869 
5870 	if (kz->uk_flags & UMA_ZFLAG_INTERNAL) {
5871 		*allocs = counter_u64_fetch(z->uz_allocs);
5872 		frees = counter_u64_fetch(z->uz_frees);
5873 		*sleeps = z->uz_sleeps;
5874 		*cachefree = 0;
5875 		*xdomain = 0;
5876 	} else
5877 		uma_zone_sumstat(z, cachefree, allocs, &frees, sleeps,
5878 		    xdomain);
5879 	for (i = 0; i < vm_ndomains; i++) {
5880 		*cachefree += ZDOM_GET(z, i)->uzd_nitems;
5881 		if (!((z->uz_flags & UMA_ZONE_SECONDARY) &&
5882 		    (LIST_FIRST(&kz->uk_zones) != z)))
5883 			*cachefree += kz->uk_domain[i].ud_free_items;
5884 	}
5885 	*used = *allocs - frees;
5886 	return (((int64_t)*used + *cachefree) * kz->uk_size);
5887 }
5888 
5889 DB_SHOW_COMMAND_FLAGS(uma, db_show_uma, DB_CMD_MEMSAFE)
5890 {
5891 	const char *fmt_hdr, *fmt_entry;
5892 	uma_keg_t kz;
5893 	uma_zone_t z;
5894 	uint64_t allocs, used, sleeps, xdomain;
5895 	long cachefree;
5896 	/* variables for sorting */
5897 	uma_keg_t cur_keg;
5898 	uma_zone_t cur_zone, last_zone;
5899 	int64_t cur_size, last_size, size;
5900 	int ties;
5901 
5902 	/* /i option produces machine-parseable CSV output */
5903 	if (modif[0] == 'i') {
5904 		fmt_hdr = "%s,%s,%s,%s,%s,%s,%s,%s,%s\n";
5905 		fmt_entry = "\"%s\",%ju,%jd,%ld,%ju,%ju,%u,%jd,%ju\n";
5906 	} else {
5907 		fmt_hdr = "%18s %6s %7s %7s %11s %7s %7s %10s %8s\n";
5908 		fmt_entry = "%18s %6ju %7jd %7ld %11ju %7ju %7u %10jd %8ju\n";
5909 	}
5910 
5911 	db_printf(fmt_hdr, "Zone", "Size", "Used", "Free", "Requests",
5912 	    "Sleeps", "Bucket", "Total Mem", "XFree");
5913 
5914 	/* Sort the zones with largest size first. */
5915 	last_zone = NULL;
5916 	last_size = INT64_MAX;
5917 	for (;;) {
5918 		cur_zone = NULL;
5919 		cur_size = -1;
5920 		ties = 0;
5921 		LIST_FOREACH(kz, &uma_kegs, uk_link) {
5922 			LIST_FOREACH(z, &kz->uk_zones, uz_link) {
5923 				/*
5924 				 * In the case of size ties, print out zones
5925 				 * in the order they are encountered.  That is,
5926 				 * when we encounter the most recently output
5927 				 * zone, we have already printed all preceding
5928 				 * ties, and we must print all following ties.
5929 				 */
5930 				if (z == last_zone) {
5931 					ties = 1;
5932 					continue;
5933 				}
5934 				size = get_uma_stats(kz, z, &allocs, &used,
5935 				    &sleeps, &cachefree, &xdomain);
5936 				if (size > cur_size && size < last_size + ties)
5937 				{
5938 					cur_size = size;
5939 					cur_zone = z;
5940 					cur_keg = kz;
5941 				}
5942 			}
5943 		}
5944 		if (cur_zone == NULL)
5945 			break;
5946 
5947 		size = get_uma_stats(cur_keg, cur_zone, &allocs, &used,
5948 		    &sleeps, &cachefree, &xdomain);
5949 		db_printf(fmt_entry, cur_zone->uz_name,
5950 		    (uintmax_t)cur_keg->uk_size, (intmax_t)used, cachefree,
5951 		    (uintmax_t)allocs, (uintmax_t)sleeps,
5952 		    (unsigned)cur_zone->uz_bucket_size, (intmax_t)size,
5953 		    xdomain);
5954 
5955 		if (db_pager_quit)
5956 			return;
5957 		last_zone = cur_zone;
5958 		last_size = cur_size;
5959 	}
5960 }
5961 
5962 DB_SHOW_COMMAND_FLAGS(umacache, db_show_umacache, DB_CMD_MEMSAFE)
5963 {
5964 	uma_zone_t z;
5965 	uint64_t allocs, frees;
5966 	long cachefree;
5967 	int i;
5968 
5969 	db_printf("%18s %8s %8s %8s %12s %8s\n", "Zone", "Size", "Used", "Free",
5970 	    "Requests", "Bucket");
5971 	LIST_FOREACH(z, &uma_cachezones, uz_link) {
5972 		uma_zone_sumstat(z, &cachefree, &allocs, &frees, NULL, NULL);
5973 		for (i = 0; i < vm_ndomains; i++)
5974 			cachefree += ZDOM_GET(z, i)->uzd_nitems;
5975 		db_printf("%18s %8ju %8jd %8ld %12ju %8u\n",
5976 		    z->uz_name, (uintmax_t)z->uz_size,
5977 		    (intmax_t)(allocs - frees), cachefree,
5978 		    (uintmax_t)allocs, z->uz_bucket_size);
5979 		if (db_pager_quit)
5980 			return;
5981 	}
5982 }
5983 #endif	/* DDB */
5984